Question

d) Find k if x-3 is the factor of k square into x cube - kx - 2​

Answer 1

Step-by-step explanation:

• EQUATION -: K^2X^3 - KX - 2
• FACTOR -: X - 3

SO , X - 3 = 0 AND X = 3

NOW , ON PUTTING THE VALUE OF X IN EQUATION......

• K^2(3)^2 - K(3) - 2 = 0

NOW ,

K^2(9) - 3K - 2 = 0

9K^2 - 3K - 2 = 0

9K^2 - 6K + 3K - 2 = 0 (FACTORISING EQUATION)

3K ( 3K - 2 ) + 1 ( 3K - 2 ) =0

(3K - 2 ) (3K + 1 ) = 0

SO , 3K - 2 = 0 AND 3K + 1 = 0

K = 2/3 AND K = -1/3

NOW , WE WILL IGNORE THE NEGATIVE VALUE OF K THAT IS -1/3.

SO THE VALUE OF K IS 2/3.

HENCE , ANSWER IS 2/3.