Question

Evaluate using suitable identity:d). 9.9²​

Answer 1

Step-by-step explanation:

9.9²

(10-0.1)²

= 10² -2 (10) (0.1) + 0.1²

= 100 -2 + 0.01

= 98.01

Hope it helps you

Answer 2

Answer:

★ Solution :-

$\sf \longmapsto 9.9^2$

$\sf \longmapsto (a - b)^2 = a^2 - 2ab + b^2$

Here,

• a = 10
• b = 0.1

$\sf \longmapsto (10 - 0.1)^2 = 10^2 - 2(10)(0.1) + 0.1^2$

$\sf \longmapsto 10^2 - 2(10)(0.1) + 0.1^2$

$\sf \longmapsto 100 - 2 + 0.01$

$\sf \longmapsto 98.01$