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Ex 7.8
Last updated at April 16, 2024 by Teachoo
Ex 7.8, 5 ∫_0^(𝜋/2)▒cos2𝑥𝑑𝑥 Let F(𝑥)=∫1▒〖𝑐𝑜𝑠 2𝑥 𝑑𝑥〗 =1/2 𝑠𝑖𝑛 2𝑥 Hence F(𝒙)=𝟏/𝟐 𝒔𝒊𝒏 𝟐𝒙 Now, ∫_0^(𝜋/2)▒〖𝒄𝒐𝒔 𝟐𝒙=𝐹(𝜋/2)−𝐹(0) 〗 =1/2 𝑠𝑖𝑛(2 × 𝜋/2)−1/2 𝑠𝑖𝑛(2 ×0) =1/2 𝑠𝑖𝑛(𝜋)−1/2 𝑠𝑖𝑛(0) =1/2 ×0−1/2 ×0 = 𝟎