Name: ______Date: ______
HW IM3 8.3.1Block: ____
8-92.Carlos is always playing games with his graphing calculator, but now his calculator has contracted a virus. The,, andfunctions on his calculator are not working. He needs to solvex3+5x2–16x–14 = 0, so he graphsy=x3+5x2–16x–14 and sees the graph below in the standard window.
- From the graph, what number appears to be an integer solution to the equation?
- Verify that your answer to part(a) is a solution.
- Since you know a solution to the equation, what is the factor associated with this solution?
- Use polynomial division to determine the other factor.
- Use your new factor to complete the following equation.
x3+ 5x2– 16x– 14 = 0
(x+7)(other factor)=0
- The “other factor” leads to two other solutions to the equation. What are the two other solutions? State all three solutions to the original equation.
8-93.Now Carlos needs to solve 2x3+ 3x2– 8x+ 3 = 0, but his calculator will still only create a graph with a standard viewing window. He sees that the graph of
y= 2x3+ 3x2– 8x+ 3 crosses thexaxis atx=1. What are all three solutions to 2x3+ 3x2– 8x+ 3 = 0?
8-94.Without actually multiplying, decide which of the following polynomials could be the product of (x– 2)(x+ 3)(x– 5). Justify your choice.
a. x3– 4x2– 11x– 5
b. 2x3– 4x2– 11x+ 30
c. x3– 4x2– 11x+ 30
d. 2x3– 4x2– 11x– 5
8-95.Consider the equation 5x2– 7x– 6 = 0 as you complete the partsbelow.
a. What are the factors of 5x2– 7x– 6?
b. What are the solutions to the equation 5x2– 7x– 6 = 0?
c. Explain the relationship between the factors of the polynomial expression and the solutions to the related equation.
8-97.Eniki has a sequence of numbers given by the formulat(n) = 4(5)n.
- What are the first three terms of Eniki’s sequence?
- Toby thinks the number 312,500 is a term in Eniki’s sequence. Is he correct? Justify your answer by either giving the term number or explaining why it is not in the sequence.
- Elisa thinks the number 94,500 is a term in Eniki’s sequence. Is she correct? Explain.
8-98.What is the equation of the line passing through the point (–2,5) that is perpendicular to the liney=–5x+2?
8-99.Which of the following binomials could be a factor ofx3– 9x2+ 19x+ 5? Explain your reasoning.
- x– 2
- x– 5
- x+ 3
- x+ 2
8-100.Now dividex3– 9x2+ 19x+ 5 by the factor that you chose in the previous problem. If it is a factor, use it and the resulting factor to determine all the roots of the polynomial. If it is not a factor, reconsider your answer to the previous problem and try a different factor.
8-101.Divide each of the following polynomials,P(x), byD(x) to write the quotientQ(x) and then rewrite the polynomial in the formP(x)=D(x)·Q(x)+R, whereRis the remainder.
a. P(x) = 2x4–x2+ 3x+ 5
D(x) =x– 1
b. P(x) =x5– 2x3+ 1
D(x) =x– 3
How are the solutions to the equation related to the leading coefficient and constant term in the original polynomial?
8-104.Evaluate each expression without using acalculator.
a. log(10)b. log()c. log(0)d. 10(2/3)log(27)