Question

find the following square by using the identities
$(2xy + 5y) {?}^{2}$
​

Answer 1

Given:

Consider the given square is

$(2xy+5y)^2$

To find:

The value of given square by using the identities.

Solution:

We know that,

$(a+b)^2=a^2+2ab+b^2$            ...(i)

We have,

$(2xy+5y)^2$

Using the identity (i), we get

$(2xy+5y)^2=(2xy)^2+2(2xy)(5y)+(5y)^2$

$(2xy+5y)^2=4x^2y^2+20xy^2+25y^2$

Therefore, the value of given square expression is $4x^2y^2+20xy^2+25y^2$.