Question

evaluate the following by using identity 2

Answer 1

(19.9)^2

= (20 - 0.1)^2

here, we use the identity ,
(a - b)^2 = a^2 - 2ab + b^2

where, a = 20 and b = 0.1

so, 20^2 - 2*20*0.1 + 0.1^2

= 400 - 4 + 0.01

hence, 396.01

Answer 2

Answer:

hi mate this is you answer

Step-by-step explanation:

in explanation

(19+0.9)² / (20-0.1/)²

biggest no. is (20- 0.1)²