Mathematics

$$\int cos^{2}\theta  d\theta $$ = ?


SOLUTION
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$$\begin{matrix} \int { { { \cos   }^{ 2 } }\theta d\theta  }  \\ \Rightarrow \int { \dfrac { { \left( { 1-\cos  2\theta  } \right) d\theta  } }{ 2 }  }  \\ \Rightarrow \int { \dfrac { 1 }{ 2 }  } d\theta -\dfrac { 1 }{ 2 } \cos  2\theta d\theta  \\ \Rightarrow \dfrac { \theta  }{ 2 } -\dfrac { 1 }{ 2 } \dfrac { { \sin  2\theta  } }{ 1 } +C \\ \Rightarrow \dfrac { \theta  }{ 2 } -\dfrac { { \sin  2\theta  } }{ 4 } +C \\  \end{matrix}$$

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Subjective Medium Published on 17th 09, 2020
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