Question

Expand (5 − 4 + 2)² using Identity​

Answer 1

Answer:

We need to expand (x+2y+4z)

2

We know appropriate identity (x+y+z)

2

=x

2

+y

2

+z

2

+2xy+2yz+2xz

Therefore, the value of (x+2y+4z)

2

is

=x

2

+(2y)

2

+(4z)

2

+2(x)(2y)+2(2y)(4z)+2(x)(4z)

=x

2

+4y

2

+16z

2

+4xy+16yz+

Answer 2

= (5-4+2)2
=(25-16-4-40-16+20)
=(-81)