Question

Can someone PLEASE give me the solution to this question, my exams in 2 days.

Answer 1

see explanation

Explanation:

the shaded area is calculated as

outer circle area - inner circle area

since CAB is a tangent to the inner circle at A then OAB = 90° and

Δ OAB is right

using Pythagoras' identity in the right triangle to express R in terms of r and d , then

R² = d² + r²

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A( outer Δ ) = πR² = π(d² + r² ) = πd² + πr²

A ( inner Δ ) = πr²

Then

shaded area = πd² + πr² - πr² = πd²