Question
upstudy study bank question image url

3. If \( 3 x^{3}-a x^{2}+2 x+1 \) has a remainder of -3 on division by \( x+2 \), find a. 4. Find both values of ' \( a \) ' for which the polynomials \( 3 x^{2}-7 x-4 \) and \( 32 x^{2}-10 x+6 \) give the same remainder on division by \( x-a \).

Ask by Pollard Burgess. in South Africa
Mar 11,2025

Upstudy AI Solution

Tutor-Verified Answer

Answer

For Problem 3, \( a = -6 \). For Problem 4, there are no real values of \( a \) that satisfy the condition.

Solution

Solve the equation by following steps: - step0: Solve for \(a\): \(3\left(-2\right)^{3}-a\left(-2\right)^{2}+2\left(-2\right)+1=-3\) - step1: Simplify: \(-27-4a=-3\) - step2: Move the constant to the right side: \(-4a=-3+27\) - step3: Add the numbers: \(-4a=24\) - step4: Change the signs: \(4a=-24\) - step5: Divide both sides: \(\frac{4a}{4}=\frac{-24}{4}\) - step6: Divide the numbers: \(a=-6\) Solve the system of equations \( 3x^{2}-7x-4=R; 32x^{2}-10x+6=R \). Solve the system of equations by following steps: - step0: Solve using the substitution method: \(\left\{ \begin{array}{l}3x^{2}-7x-4=R\\32x^{2}-10x+6=R\end{array}\right.\) - step1: Rewrite the expression: \(\left\{ \begin{array}{l}R=3x^{2}-7x-4\\32x^{2}-10x+6=R\end{array}\right.\) - step2: Substitute the value of \(R:\) \(32x^{2}-10x+6=3x^{2}-7x-4\) - step3: Move the expression to the left side: \(32x^{2}-10x+6-\left(3x^{2}-7x-4\right)=0\) - step4: Calculate: \(29x^{2}-3x+10=0\) - step5: Solve using the quadratic formula: \(x=\frac{3\pm \sqrt{\left(-3\right)^{2}-4\times 29\times 10}}{2\times 29}\) - step6: Simplify the expression: \(x=\frac{3\pm \sqrt{\left(-3\right)^{2}-4\times 29\times 10}}{58}\) - step7: Simplify the expression: \(x=\frac{3\pm \sqrt{-1151}}{58}\) - step8: The expression is undefined: \(x \notin \mathbb{R}\) - step9: The system of equations has no solution in the set of real numbers: \(\left(R,x\right) \notin \mathbb{R}^{2}\) - step10: Alternative Form: \(\textrm{No real solution}\) Let's solve the problems step by step. ### Problem 3 We need to find the value of \( a \) such that the polynomial \( 3x^{3} - ax^{2} + 2x + 1 \) has a remainder of -3 when divided by \( x + 2 \). According to the Remainder Theorem, the remainder of a polynomial \( f(x) \) when divided by \( x - c \) is \( f(c) \). Here, we need to evaluate the polynomial at \( x = -2 \): \[ f(-2) = 3(-2)^{3} - a(-2)^{2} + 2(-2) + 1 \] Calculating \( f(-2) \): \[ f(-2) = 3(-8) - a(4) - 4 + 1 = -24 - 4a - 4 + 1 = -27 - 4a \] Setting this equal to -3 (the given remainder): \[ -27 - 4a = -3 \] Now, solving for \( a \): \[ -4a = -3 + 27 \] \[ -4a = 24 \] \[ a = -6 \] Thus, the value of \( a \) is \( -6 \). ### Problem 4 We need to find the values of \( a \) for which the polynomials \( 3x^{2} - 7x - 4 \) and \( 32x^{2} - 10x + 6 \) give the same remainder when divided by \( x - a \). Let the remainder when dividing by \( x - a \) be \( R \). We can express this as: 1. \( 3a^{2} - 7a - 4 = R \) 2. \( 32a^{2} - 10a + 6 = R \) Setting these two equations equal to each other: \[ 3a^{2} - 7a - 4 = 32a^{2} - 10a + 6 \] Rearranging gives: \[ 3a^{2} - 32a^{2} + 10a - 7a - 4 - 6 = 0 \] \[ -29a^{2} + 3a - 10 = 0 \] This is a quadratic equation, but upon solving, we find that there are no real solutions. Therefore, there are no values of \( a \) for which the two polynomials give the same remainder when divided by \( x - a \). ### Summary of Results - For Problem 3, \( a = -6 \). - For Problem 4, there are no real solutions for \( a \).

Answered by UpStudy AI and reviewed by a Professional Tutor

error msg
Explain
Simplify this solution

Bonus Knowledge

To find the value of \( a \) such that the polynomial \( 3 x^{3}-a x^{2}+2 x+1 \) has a remainder of -3 when divided by \( x+2 \), we can use the Remainder Theorem. This theorem states that the remainder of \( f(x) \) when divided by \( x-c \) is equal to \( f(c) \). So, we evaluate at \( x = -2 \): \[ f(-2) = 3(-2)^{3} - a(-2)^{2} + 2(-2) + 1 \] Calculating this step by step: \[ f(-2) = 3(-8) - a(4) - 4 + 1 = -24 - 4a - 3 \] Setting \( f(-2) = -3 \): \[ -24 - 4a - 3 = -3 \\ -27 - 4a = -3 \\ -4a = 24 \\ a = -6 \] For the second part, we need to find both values of \( a \) such that the polynomials \( 3 x^{2}-7 x-4 \) and \( 32 x^{2}-10 x+6 \) give the same remainder when divided by \( x-a \). Using the Remainder Theorem again, we need: \[ f(a) = g(a) \] Where \( f(x) = 3 x^{2} - 7 x - 4 \) and \( g(x) = 32 x^{2} - 10 x + 6 \). Setting equality: \[ 3a^{2} - 7a - 4 = 32a^{2} - 10a + 6 \] Rearranging gives: \[ 0 = 29a^{2} - 3a + 10 \\ 29a^{2} - 3a + 10 = 0 \] Using the quadratic formula \( a = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \): \[ a = \frac{3 \pm \sqrt{(-3)^{2} - 4(29)(10)}}{2(29)} \\ = \frac{3 \pm \sqrt{9 - 1160}}{58} \\ = \frac{3 \pm \sqrt{-1151}}{58} \] Since we have a negative number under the square root, this indicates \( a \) has complex values. Simplifying, we find: \[ a = \frac{3 \pm i\sqrt{1151}}{58} \] This gives us our final expressions for \( a \).

Try Premium now!
Try Premium and ask Thoth AI unlimited math questions now!
Maybe later Go Premium
Study can be a real struggle
Why not UpStudy it?
Select your plan below
Premium

You can enjoy

Start now
  • Step-by-step explanations
  • 24/7 expert live tutors
  • Unlimited number of questions
  • No interruptions
  • Full access to Answer and Solution
  • Full Access to PDF Chat, UpStudy Chat, Browsing Chat
Basic

Totally free but limited

  • Limited Solution
Welcome to UpStudy!
Please sign in to continue the Thoth AI Chat journey
Continue with Email
Or continue with
By clicking “Sign in”, you agree to our Terms of Use & Privacy Policy