Question

Q. If x + 1 and x - 1 are factor of mx3 + x2 - 2x + n, find the value of m and
n.​

Answer 1

Step-by-step explanation:

let x=1

mx³+x²-2x+n=0

m(1)³+(1)²-2(1)+n=0

m+1-2+n=0

m+n-1=0=>>m+n=1----(1)

for x=-1

m(-1)³+(-1)²-2(-1)+n=0

-m+1+2+n=0=>>m-n=3---(2)

add (1)and(2)

2m=4

m=2

put m=2 in (1)

2+n=1

n=-1

(m,n)=(2,-1)

Answer 2

Answer:

Hey

Step-by-step explanation:

let x=1

mx³+x²-2x+n=0

m(1)³+(1)²-2(1)+n=0

m+1-2+n=0

m+n-1=0=>>m+n=1----(1)

for x=-1

m(-1)³+(-1)²-2(-1)+n=0

-m+1+2+n=0=>>m-n=3---(2)

add (1)and(2)

2m=4

m=2

put m=2 in (1)

2+n=1

n=-1

(m,n)=(2,-1)