503,237 views
20 votes
20 votes
Math is uhhh confusing to me please help

Math is uhhh confusing to me please help-example-1
User CWright
by
2.9k points

2 Answers

24 votes
24 votes

Answer:

x = 1, x = 2, x = 5

Explanation:

Divide f(x) by (x - 2) using Synthetic division

2 | 1 - 8 17 - 10

↓ 2 - 12 10

--------------------------

1 - 6 5 0 ← remainder

quotient = x² - 6x + 5 = (x - 1)(x - 5)

f(x) = (x - 1)(x - 2)(x - 5)

To find the zeros let f(x) = 0 , that is

(x - 1)(x - 2)(x - 5) = 0

Equate each factor to zero and solve for x

x - 1 = 0 ⇒ x = 1

x - 2 = 0 ⇒ x = 2

x - 5 = 0 ⇒ x = 5

User Chkdsk
by
3.0k points
17 votes
17 votes

Answer:

x = 1, x = 2, x = 5

Explanation:


f(x)=x^3-8x^2+17x-10

if
x - 2 is a factor of
f(x), then


f(x)=(x-2)(x^2+bx+5)

Expand brackets:


\implies f(x)=x^3+bx^2+5x-2x^2-2bx-10

Combine like terms:


\implies f(x)=x^3+(b-2)x^2+(5-2b)x-10

Compare coefficients for
x^2:


b-2=-8


\implies b=-6

Therefore,


f(x)=(x-2)(x^2-6x+5)

Factoring
(x^2-6x+5):


\implies f(x)=(x-2)(x-1)(x-5)

To find the zeros of
f(x), set the function to zero and solve for
x:


\implies f(x)=0\\\\\implies(x-2)(x-1)(x-5)=0\\\\\implies x=2,x=1,x=5

User Mikelis Kaneps
by
3.0k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.