Ans
1
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dt=cosxdx, and cos^3x can be written as cos^2x.cosx. so cosx was consumed by dt and cos^2x can be wriiten as (1-sin^2x). t is equal to sin x so the value of sin^2x will be t^2. so cos^2x became (1-t^2).
thats how cos^3x became (1-t^2)dt
6 years ago
by
Rudransh Tyagi