Question

Find the value of a and b, if x+1 and x+2 are factor of x3

-3x2

-2ax+b​

Answer 1

Answer:

a= 8

b= -12

Step-by-step explanation:

if  x+1 and x+2 are factor of x3 -3x2 -2ax+b​ the on putting the value of the -1 and -2 the equation will become 0.  

So,

i. putting x= -1

equation will become 2a + b= 4 ----------------{1}

ii. putting x= -2

equation will become 4a + b= 20----------------{2}

now we can solve this equation as they are in linear equation in two variable -

subtracting i from ii, we get

a= 8

putting a in any of the above equation = b= -12