Pt1420 Unit 2 Study Guide

420 Words2 Pages

Chase Williams
Ms. Haramis
Task 1 Q&A
Complete the following exercises by applying polynomial identities to complex numbers.
1. Factor x2 + 64. Check your work.
2. Factor 16x2 + 49. Check your work.
3. Find the product of (x + 9i)2.
4. Find the product of (x − 2i)2.
5. Find the product of (x + (3+5i))2.
Answers
1. x^2 +64=
Answer: (x+8i)(x-8i)
2. 16x^2+49=
Answer: (4x+7i)(4x-7i)
3. (x+9i)^2= (x+9i)(x+9i= x^2+9ix+9ix+81i^2=x^2+18ix+(-81)=
Answer: x^2+18ix-81
4. (x-2i)^2=(x-2i)(x-2i)=x^2-2ix-2ix+4i^2=x^2-4ix+(-4)=
Answer: x^2-4ix-4
5. (x+(3+5i))^2=(x+(3+5i)(x+(3+5i)
X^2+3x+5ix+3x+9+15i+5ix+15i+25i^2=x^2+6x+10ix+30i+25i^2+9=
Answer: X^2+6x+10ix+30i-25+9= x^2+6x+10ix+30i-16

Task 2 Q&A
Expand the following using the Binomial Theorem and …show more content…

(x + 2)6
2. (x − 4)4
3. (2x + 3)5
4. (2x − 3y)4
5. In the expansion of (3a + 4b)8, which of the following are possible variable terms? Explain your reasoning. a2b3; a5b3; ab8; b8; a4b4; a8; ab7; a6b5
Answers
1. (x + …show more content…

(2x − 3y)^4=16x^4-96x^3y+216x^2y^2-216xy3+81y^4
5. The possible variable terms would have to be a2b3; a5b3; ab8; b8; a4b4; a8; ab7; a6b5 because the exponents of each one of the terms all add up to 8.
Task 3 Q&A
Using the Fundamental Theorem of Algebra, complete the following:

1. Determine how many, what type, and find the roots for f(x) = x4 + 21x2 − 100.
2. Determine how many, what type, and find the roots for f(x) = x3 − 5x2 − 25x + 125.
3. The following graph shows a seventh-degree polynomial: graph of a polynomial that touches the x axis at negative 5, crosses the x axis at negative 1, crosses the y axis at negative 2, crosses the x axis at 4, and crosses the x axis at 7.
Part 1: List the polynomial’s zeroes with possible multiplicities.
Part 2: Write a possible factored form of the seventh degree function.

4. Without plotting any points other than intercepts, draw a possible graph of the following polynomial: f(x) = (x + 8)3(x + 6)2(x + 2)(x − 1)3(x − 3)4(x − 6).
Answers
1. There will be 4 roots total, Two real and two complex, and the roots are x=-2, x=2, x=5i, x=-5i
2. There will be 3 roots total, two real, and the roots are x=5 with a multiplicity of 2, and