Simplify the expression (2x^3)(4x^5).
- 6x^8
- 6x^15
- 8x^8 Correct answer.
- 8x^15
Explanation
Multiply the numerical coefficients: 2 times 4 equals 8. When multiplying powers with the same base, add the exponents, so x^3 times x^5 gives x^(3+5) = x^8.
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Multiply the numerical coefficients: 2 times 4 equals 8. When multiplying powers with the same base, add the exponents, so x^3 times x^5 gives x^(3+5) = x^8.
This is a difference of two squares, a^2 - b^2 = (a - b)(a + b), with a = x and b = 3. Expanding (x - 3)(x + 3) returns x^2 - 9.
Subtract 3x from both sides to get 2x - 7 = 9. Add 7 to both sides to get 2x = 16, then divide by 2 to obtain x = 8.
Subtract 3 from both sides to get -2x > 8. Dividing both sides by -2 reverses the inequality direction, giving x < -4.
Absolute value gives the distance from zero, so |3 - 8| = |-5| = 5 and |2 - 9| = |-7| = 7. Their sum is 5 + 7 = 12.
Factor the numerator as (x - 2)(x + 2) and cancel the common factor x - 2, leaving x + 2. The cancellation is invalid at x = 2, where the original denominator is zero, so that value must be excluded.
Factor the quadratic as (x - 2)(x - 3) = 0. Setting each factor equal to zero gives x = 2 or x = 3.
The slope is (13 - 5)/(6 - 2) = 8/4 = 2. Using point-slope form with (2, 5): y - 5 = 2(x - 2), which simplifies to y = 2x + 1.
Factor as (x - 3)(x + 2) < 0; the critical values are x = -2 and x = 3. The parabola opens upward, so it lies below the x-axis between its roots, giving the open interval (-2, 3).
Divide by the known factor x - 2 to get x^2 - 2x - 3, which factors as (x - 3)(x + 1). The complete factorization is therefore (x - 2)(x - 3)(x + 1).
Rewrite 27 as 3^3, so the right side becomes 3^(3x - 3). Equating exponents gives x + 1 = 3x - 3, so 4 = 2x and x = 2.
Convert the logarithmic equation to exponential form: x + 5 = 2^3 = 8. Subtracting 5 gives x = 3, which is valid because x + 5 = 8 is positive.
Multiply both sides by (x - 1)(x + 1) to get 2(x + 1) + 3(x - 1) = x^2 - 1, which simplifies to x^2 - 5x - 2 = 0. The quadratic formula gives x = (5 ± √33)/2, and neither value makes a denominator zero, so both are valid.
Adding the two equations eliminates y and gives 6x = 18, so x = 3. Substituting into 2x + 3y = 12 gives 6 + 3y = 12, so y = 2.
An inequality of the form |u| ≤ c is equivalent to -c ≤ u ≤ c, so -7 ≤ 2x - 5 ≤ 7. Adding 5 gives -2 ≤ 2x ≤ 12, and dividing by 2 gives -1 ≤ x ≤ 6, that is, [-1, 6].
The composition (f ∘ g)(x) means f(g(x)), so substitute 2x + 1 into f: (2x + 1)^2 - 3(2x + 1). Expanding gives 4x^2 + 4x + 1 - 6x - 3 = 4x^2 - 2x - 2.
The denominator x^2 - 4 = (x - 2)(x + 2) is zero at x = ±2, and the numerator is nonzero there, so these are vertical asymptotes. Because the numerator and denominator have equal degree, the horizontal asymptote is the ratio of leading coefficients, y = 1/1 = 1.
Let u = x^2, so the equation becomes u^2 - 5u + 4 = 0, which factors as (u - 1)(u - 4) = 0. Thus x^2 = 1 or x^2 = 4, giving x = ±1 or x = ±2.
Factor the denominator as (x - 2)(x + 2) and cancel the common factor x + 2, leaving 1/(x - 2). Both x = 2 and x = -2 must be excluded because each makes the original denominator zero.
Taking the common logarithm of both sides gives 3x log 2 = log 5. Dividing by 3 log 2 isolates x = (log 5)/(3 log 2).
A quadratic has exactly one real solution when its discriminant b^2 - 4ac equals zero. Here k^2 - 36 = 0, so k^2 = 36 and k = ±6.
By the Remainder Theorem, the remainder equals p(3). Computing 2(27) - 3(9) - 11(3) + 6 = 54 - 27 - 33 + 6 = 0, so x - 3 is a factor.
The critical values are x = 1 (numerator zero) and x = -3 (denominator zero). Testing intervals shows the expression is positive on (-∞, -3) and on (1, ∞); x = 1 is included since the inequality is non-strict, while x = -3 is excluded because the expression is undefined there.
Complete the square: x^2 + 4x + 7 = (x^2 + 4x + 4) + 3 = (x + 2)^2 + 3. Since the squared term is nonnegative, the minimum value is 3, occurring at x = -2.
Use the identity x^2 + y^2 = (x + y)^2 - 2xy. Substituting gives 49 - 20 = 29, which matches x = 5 and y = 2.
Apply the power of a product rule: (2x^3y^{-2})^3 = 2^3 (x^3)^3 (y^{-2})^3 = 8 x^9 y^{-6}. Rewrite with a positive exponent: 8x^9/y^6. The coefficient 2 must also be cubed, and the exponents multiply.
Factor by grouping: 6x^2 + 9x - 2x - 3 = 3x(2x+3) -1(2x+3) = (2x+3)(3x-1). Thus 3x-1 is a factor. Checking the other options by substitution or multiplication shows they do not divide the polynomial evenly.
Factor numerator and denominator: (x+5)(x-3) / [(x-3)(x+3)]. Cancel the common factor (x-3), leaving (x+5)/(x+3). The original expression is undefined at x=3 and x=-3, so the simplified form must exclude both; however, x=-3 makes the simplified denominator zero, so the restriction x≠3 is the one that must be stated explicitly for the simplified form. The domain of the original expression excludes both 3 and -3.
Square both sides: 2x+3 = x^2, so x^2 - 2x - 3 = 0, which factors as (x-3)(x+1)=0. The solutions are x=3 and x=-1. Check in the original equation: x=3 gives √9=3, true; x=-1 gives √1=1, but the right side is -1, so it is extraneous. Thus the only solution is x=3.
A quadratic equation has exactly one real solution when its discriminant b^2-4ac equals zero. For x^2-6x+9=0, the discriminant is (-6)^2-4(1)(9)=36-36=0, so there is one real solution (a double root). The other equations have discriminants 4, -4, and 36, giving two, zero, and two real solutions respectively.
The second equation is exactly twice the first: 2(3x-2y)=6x-4y and 2(7)=14. Thus the two equations represent the same line, so every point on that line satisfies both. Therefore there are infinitely many solutions, not a unique ordered pair.
The critical points are x=2 and x=-4. Test intervals: for x<-4, both factors are negative, product positive; for -4<x<2, one negative and one positive, product negative; for x>2, both positive, product positive. Since the inequality is ≤0, include the endpoints where the product is zero, giving [-4, 2].
An absolute value inequality of the form |A| ≥ b splits into A ≤ -b or A ≥ b. So 3x-4 ≤ -5 or 3x-4 ≥ 5. Solving gives 3x ≤ -1 ⇒ x ≤ -1/3, or 3x ≥ 9 ⇒ x ≥ 3. Thus the solution is (-∞, -1/3] ∪ [3, ∞).
Recognize the difference of cubes: x^3 - 8 = (x-2)(x^2+2x+4). Dividing by (x-2) gives x^2+2x+4, provided x≠2 because the original expression is undefined at x=2. The quadratic factor is correct because (x-2)(x^2+2x+4)=x^3+2x^2+4x-2x^2-4x-8=x^3-8.
Factor by grouping: x^2(2x-3) -4(2x-3) = (2x-3)(x^2-4) = (2x-3)(x-2)(x+2). Setting each factor to zero gives x=3/2, x=2, and x=-2. Thus the solution set is {-2, 2, 3/2}.
Bring all terms to one side: (x+1)/(x-3) - 2 ≤ 0 ⇒ (x+1 - 2x + 6)/(x-3) ≤ 0 ⇒ (-x+7)/(x-3) ≤ 0 ⇒ (x-7)/(x-3) ≥ 0. The critical points are 3 (undefined) and 7 (zero). Sign analysis gives positive on (-∞,3) and (7,∞), zero at 7. Including x=7 but excluding x=3 yields (-∞,3) ∪ [7,∞).
Use the product rule: log_3(9x^2) = log_3 9 + log_3(x^2). Since log_3 9 = 2 and log_3(x^2) = 2 log_3 x for x>0, the expression becomes 2 + 2 log_3 x. The coefficient 2 applies to the logarithm of x, not to the constant term.
Treat as a quadratic in x^2: let u=x^2, then u^2 - 5u + 4 = (u-1)(u-4). So p(x) = (x^2-1)(x^2-4). Each quadratic factors further as a difference of squares: (x-1)(x+1)(x-2)(x+2). This is the complete factorization into linear factors over the reals.
The least common denominator is (x-2)(x+2)=x^2-4. Multiply both sides by the LCD: x(x+2) + 3(x-2) = 8. Expand: x^2+2x+3x-6=8 ⇒ x^2+5x-14=0 ⇒ (x+7)(x-2)=0. So x=-7 or x=2. But x=2 makes the original denominators zero, so it is extraneous. Thus x=-7 is the only solution. However, the options list x=1, not -7; this indicates an error in the question. Let's re-evaluate: perhaps the equation is different. The given equation: x/(x-2) + 3/(x+2) = 8/(x^2-4). Multiplying by (x-2)(x+2): x(x+2) + 3(x-2) = 8. x^2+2x+3x-6=8 => x^2+5x-14=0 => (x+7)(x-2)=0. Solutions: x=-7 or x=2; x=2 is extraneous. So the only solution is x=-7, which is not among the options. This question is flawed. I need to rewrite it to have a correct option among the choices. Let me adjust the equation so that one of the options is correct. For example, change the right side to 6/(x^2-4). Then x(x+2)+3(x-2)=6 => x^2+2x+3x-6=6 => x^2+5x-12=0, which does not factor nicely. Alternatively, change the numerator 3 to 1: x/(x-2) + 1/(x+2) = 8/(x^2-4). Then x(x+2)+(x-2)=8 => x^2+2x+x-2=8 => x^2+3x-10=0 => (x+5)(x-2)=0 => x=-5 or x=2; extraneous x=2, so x=-5 not in options. Hmm. I need to design a question that yields one of the options. Let's choose an equation that gives x=1. For instance, x/(x-2) + 3/(x+2) = 8/(x^2-4) gave x=-7. If I change 8 to 2: x(x+2)+3(x-2)=2 => x^2+2x+3x-6=2 => x^2+5x-8=0, not nice. Change 3 to 1 and 8 to 6: x(x+2)+(x-2)=6 => x^2+2x+x-2=6 => x^2+3x-8=0, not nice. Change 3 to 2 and 8 to 6: x(x+2)+2(x-2)=6 => x^2+2x+2x-4=6 => x^2+4x-10=0, not nice. Change 3 to 4 and 8 to 6: x(x+2)+4(x-2)=6 => x^2+2x+4x-8=6 => x^2+6x-14=0, not nice. I need a factorable quadratic. Let's set up so that the solution is x=1. Suppose the equation is x/(x-2) + A/(x+2) = B/(x^2-4). Then x(x+2)+A(x-2)=B => x^2+(2+A)x -2A -B=0. We want x=1 to be a solution, so 1+(2+A)-2A-B=0 => 3 -A -B=0 => B=3-A. Also we want the other solution to be extraneous, i.e., x=2 or x=-2. If we want x=2 to be the extraneous solution, then plugging x=2 into the quadratic: 4+2(2+A)-2A-B=0 => 4+4+2A-2A-B=0 => 8-B=0 => B=8. Then from B=3-A, we get 8=3-A => A=-5. So equation: x/(x-2) -5/(x+2) = 8/(x^2-4). Then multiplying: x(x+2)-5(x-2)=8 => x^2+2x-5x+10=8 => x^2-3x+2=0 => (x-1)(x-2)=0 => x=1 or x=2; x=2 extraneous, so x=1. That works! So I can use that equation. Let me rewrite the question with that equation. So the equation is x/(x-2) - 5/(x+2) = 8/(x^2-4). Then the solution is x=1. The options can include x=1, x=2, x=-2, x=0. That will work. So I'll change the question to that. The explanation will show the work and note that x=2 is extraneous. The correct option is x=1. I'll set correctIndex accordingly. So I'll replace the question text and explanation. I'll keep the options as x=1, x=2, x=-2, x=0. The correct answer is x=1. The wrong explanations: x=2 is extraneous, x=-2 makes denominator zero, x=0 does not satisfy. So I'll rewrite the question. I'll make sure the explanation is clear. This will be a medium difficulty question on rational equations. I'll set topic to rational-equations. I'll set skill to application. I'll set difficulty to medium. I'll set correctIndex to 0. I'll set wrongExplanations for 1,2,3. I'll ensure the explanation is at least 15 words. I'll write it out. So final question: "The equation x/(x - 2) - 5/(x + 2) = 8/(x^2 - 4) is solved. Which value of x satisfies the equation?" Options: ["x = 1", "x = 2", "x = -2", "x = 0"]. CorrectIndex 0. Explanation: "Multiply both sides by the LCD (x-2)(x+2): x(x+2) - 5(x-2) = 8. Expand: x^2+2x-5x+10=8 ⇒ x^2-3x+2=0 ⇒ (x-1)(x-2)=0. So x=1 or x=2. But x=2 makes the original denominators zero, so it is extraneous. The only solution is x=1." That's good. Wrong explanations: for 1: "x=2 satisfies the cleared equation but makes the original denominator x-2 zero, so it is extraneous." For 2: "x=-2 makes the denominator x+2 zero, so it is not in the domain." For 3: "Substituting x=0 gives 0/(-2) -5/2 = -5/2, while the right side is 8/(-4)=-2; they are not equal." That works. I'll use this. I'll ensure the options are mutually exclusive and only one correct. Good.
By the Remainder Theorem, the remainder is p(2). Compute p(2) = 2(16) - 7(8) + 5(4) + 4(2) - 4 = 32 - 56 + 20 + 8 - 4 = 0. So the remainder is 0, meaning x-2 is a factor of p(x).
Substitute x = −2 into the expression: 3(−2)² − 5(−2) + 2 = 3(4) + 10 + 2 = 12 + 10 + 2 = 24. Careful sign handling on the squared term and on −5(−2) is the key step.
A square root requires a nonnegative radicand, so 7 − 2x ≥ 0. Solving gives −2x ≥ −7, and dividing by a negative reverses the inequality to x ≤ 3.5.
By definition (f ∘ g)(x) = f(g(x)), so substitute g(x) into f: (2x − 3)² + 1. Expanding gives 4x² − 12x + 9 + 1 = 4x² − 12x + 10.
Odd functions satisfy f(−x) = −f(x) for every x in the domain, which makes the graph invariant under a 180-degree rotation about the origin. Even functions, by contrast, satisfy f(−x) = f(x) and reflect across the y-axis.
In vertex form a(x − h)² + k, the value h gives a horizontal shift of h units and k gives a vertical shift of k units. Here h = 4 shifts the graph right 4, and k = 6 shifts it up 6.
Set y = 5x − 2 and solve for x: add 2 to get y + 2 = 5x, then divide by 5 to get x = (y + 2)/5. Interchanging variables gives f⁻¹(x) = (x + 2)/5.
The average rate of change is [f(4) − f(1)]/(4 − 1). Here f(4) = 16 − 12 = 4 and f(1) = 1 − 3 = −2, so the quotient is (4 − (−2))/3 = 6/3 = 2.
A relation is a function when each x-value produces exactly one y-value. The equation y = |x| − 4 assigns a single output to every input, while the others give two y-values for many x-values.
The quotient function is defined by (f/g)(x) = f(x)/g(x). Evaluate each part at x = 3: f(3) = 9 + 6 = 15 and g(3) = 2, so the quotient is 15/2.
For a quadratic ax² + bx + c, the vertex x-coordinate is −b/(2a) = 6/2 = 3. Then f(3) = 9 − 18 + 5 = −4, and because a = 1 > 0 the parabola opens upward, making the vertex a minimum.