Question

Find the value of k if (x+1)is a factor of the following 4x^3+3x^2-42+k

Answer 1

Answer:

x+1=0

x=-1

4(-1)^3+3(-1)^2-42+k=0

-4+3-42+k=0

-43+k=0

k=43

Answer 2

if x+1 is factor, then x+1=0

x=-1

f(x)=4x^3+3x^2-42+k

f(-1)= 4*(-1)^3+3*(-1)^2-42+k=0

-4+3-42+k=0

-1-42 = -k

-43=-k

k=43

hence value of k is 43

•if in question its given that something is factor of any polynomial just.make it equal to 0 and find the value and then.put it in f(x) and after putting in f(x) just solve and get the answer