Question

(3.
Factorise the following
(i) 4x2 +9y? +257 +12xy + 30yz +202%
(ii) 25x + 4y +97 - 202y +1242 - 3012​

Answer 1

Answer:

We have

4x

2

+9y

2

+25z

2

−12xy−30yz+20zx

=[(2x)

2

+(−3y)

2

+(5z)

2

+2(2x)(−3y)+2(−3y)(5z)+2(5z)(2x)]

Comparing with the identity V,

(x+y+z)

2

≡x

2

+y

2

+z

2

+2xy+2yz+2zx, we get

=(2x−3y+5z)

2

=(2x−3y+5z)(2x−3y+5z).