Question

If (x+l) ( x+m) = x^2 + 4x + 2 find the value of (l^2 + m^2) and(l+m)^2 ?

Answer 1

Step-by-step explanation:

(x+l)(x+m)

=x²+lx + mx+ ml

=x²+(m+l)x+ml

comparing the coefficient we ge that

m+l=4----(1)

and

ml=2----(2)

so from equation 1

(m+l)²=16------(3)

we know that

(m+l)²= m²+l²+2ml by algebraic identity

m²+l²=(m+l)²-2ml

from (3)&(2)

m²+l²=16-(2*2)

m²+l²=12