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Question

Please help me understand this calculus 2 u substution question it confuses me

Answer 1

If we let u = cos(θ), then du = -sin(θ) dθ.

Then, ∫sin(θ) cos¹⁷⁷⁶(θ) dθ = ∫-u¹⁷⁷⁶ du =

u¹⁷⁷⁷/1777 + C =

cos¹⁷⁷⁷(θ)/1777 + C

Answer 2