Question

\({[ (0.1)^2 − (0.01)^2 ] \over 0.0001} + 2 \)  is equal to - 
1. 101
2. 1.01
3. 100
4. 1.10

Answer 1

Correct Answer - Option 1 : 101

Algebric Identities:

a² - b² = (a+b)(a-b)  

Calculations:

\({[ (0.1)^2 − (0.01)^2 ] \over 0.0001} + 2 \)

⇒ \({[ (0.1 + 0.01) (0.1 − 0.01) ] \over 0.0001} + 2 \)

⇒ \({[ (0.1 + 0.01) (0.1 − 0.01) ] \over 0.0001} + 2 \)

⇒ \({[ (0.11) (0.09) ] \over 0.0001} + 2 \)

⇒ \({[ (0.0099) ] \over 0.0001} + 2 \)

⇒ \({[ (0.0099) ] \over 0.0001} + 2 \)

⇒ 101