Question

Find (42)² without actual multiplication.
Please can you explain step by step..
For class 8th..

Answer 1

Answer:

1764

We can use the identity: (a+b)^2= a^2 + b^2+ 2ab, to find the square of 42.

42 = 40 + 2

42^2 = (40 + 2)^2

Using the formula, we know;

(40)^2= 40^2 + 2^2 + 2(40)(2)

(40)^2 = 1600 + 4 + 160

(40)^2 = 1764