Find the quotient when (a-1 - 1) is divided by (a

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Find the quotient when (a^-1 - 1) is divided by (a - 1).

1. 2/a
2. 2a
3. a/2
4. -1/a

Correct Option: D

Given equation is
a^-1 - 1
Apply the law of Fractional Exponents and Laws of Exponents
x^-y = 1/x^y
⇒ a^-1 - 1 = 1/a - 1
⇒ a^-1 - 1 = (1 - a)/a
Now divide by a - 1 in above equation,
⇒ ( a^-1 - 1 ) ÷ (a - 1) = (1 - a)/a ÷ (a - 1)
⇒ ( a^-1 - 1 ) ÷ (a - 1) = (1 - a)/a x 1/ (a - 1)
⇒ ( a^-1 - 1 ) ÷ (a - 1) = -1x (a - 1)/a x 1/ (a - 1)
⇒ ( a^-1 - 1 ) ÷ (a - 1) = -1/a
∴ Required quotient = -1/a.