Question

use direct method to evaluate the following products

Answer 1

The algebraic formula for this is-:
(a-b)*(a+b)=a^2 - b^2.

1.). (z-2/3)(z+2/3)= z^2 - (2/3)^2.
=z^2 - 4/9.


2.) (3/5a +1/2)(3/5a -1/2)= (3/5a)^2 - (1/2)^2.
=9/25a^2 - 1/4.

Hope this helps.

Answer 2

hii!!!

here's ur answer...

in both the parts, third identity is used.

which is (a+b)(a-b)=a²-b²

1. (z-2/3)(z+2/3)

= (z)²-(2/3)²

= z²-4/9

2. (3/5a+1/2)(3/5a-1/2)

= (3/5a)²-(1/2)²

= 9/25a²-1/4

hope this helps..!