Question

Evaluate using suitable identities.
(1) 43 x 45 ​

Answer 1

(43×45)= ( 40+3 ) ( 40+5)

Using identity = (a+b)(a+c)

a^2+(b+c)a +bc

(40+3)(40+5) = (40)^2+(3+5)40+(3×5)

=. 1600+8(40)+15

= 1600+320+15

= 1935