Question

7.
Find the following by using Identity-I.
(i) (2x + 5)2
(ii) (8x + 3y) 2
3
a +
5
3
(iv) (7pq + 4ab)
(v)
(0.2x + 1.5y)2
Wi)
(2m² + 3n2)2​

Answer 1

Answer: (i) (2x)²+ (2*2x*5)+ (5)²

=4x²+ 20x+ 25

(ii) (8x)²+ (2*8x*3y)+ (3y)²

=64x²+ 48xy+ 9y²

(iv) (7pq)²+ (2*7pq*4ab)+ (4ab)²

= 49p²q²+ 56abpq+ 16a²b²

(v) (0.2)²+ (2*0.2*1.5)+ (1.5)²

=0.04+ 0.6+ 1.25

= 1.89

(vi) (2m²)²+ (2*2m²*3n²)+ (3n²)²

= 4m^4+ 12m²n²+ 9m^4