Question

find k if x-2 is a factor of 3xcube +4xsquare -5x -5k

Answer 1

Step-by-step explanation:

The value of k is 6

I explained it step by step ok

Hope it helps you

Answer 2

ANSWER:

• Value of k is 6.

GIVEN:

• P(x) = 3x³+4x²-5x-5k
• (x-2) is the factor of P(x)

TO FIND

• Value of 'k'.

SOLUTION:

=> P(x) = 3x³-4x²-5x-5k

Since, (x-2) is the zero of the polynomial . So if we put x = 2 in place of x we will get the remainder = 0.

=> 3(2)³+4(2)²-5(2)-5k = 0

=> 24+16-10-5k = 0

=> 30-5k = 0

=> 5k = 30

=> k = 30/5

=> k = 6.

Value of k is 6.

NOTE:

Some important formulas:

(a+b)² = a²+b²+2ab

(a-b)² = a²+b²-2ab

(a+b)(a-b) = a²-b²

(a+b)³ = a³+b³+3ab(a+b)

(a-b)³ = a³-b³-3ab(a-b)

a³+b³ = (a+b)(a²+b²-ab)

a³-b³ = (a-b)(a²+b²+ab)

(a+b)² = (a-b)²+4ab

(a-b)² = (a+b)²-4ab