Question

Find the square f 3x+2y

Answer 1

Step-by-step explanation:

3x+2y)2+(3x−2y)2

Using identity:

(a+b)2=a2+b2+2ab

(a−b)2=a2+b2−2ab

Therefore,

(3x+2y)2+(3x−2y)2

=[(3x)2+(2y)2+2(3x)(2y)]+[(3x)2+(2y)2−2(3x)(2y)]

=[9x2+4y2+12xy]+[9x2+4y2−12xy]

=9x2+4y2+12xy+9x2+4y2−12xy

=18x2+8y2

=2(9x2+4