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 Multiple Choice QuestionsShort Answer Type

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161.

Show that:
integral subscript 0 superscript straight pi over 2 end superscript fraction numerator cos space straight x over denominator sin space straight x space plus space cos space straight x end fraction dx



Let I = integral subscript 0 superscript straight pi over 2 end superscript fraction numerator cos space straight x over denominator sin space straight x plus space cos space straight x end fraction dx                     ...(1)
Then straight I space equals space integral subscript 0 superscript straight pi over 2 end superscript fraction numerator cos space open parentheses begin display style straight pi over 2 end style minus straight x close parentheses over denominator sin open parentheses begin display style straight pi over 2 end style minus straight x close parentheses plus cos open parentheses begin display style straight pi over 2 end style minus straight x close parentheses end fraction dx space space space space open square brackets because space integral subscript 0 superscript straight a straight f left parenthesis straight x right parenthesis space dx space equals space integral subscript 0 superscript straight a straight f left parenthesis straight a minus straight x right parenthesis space dx close square brackets
therefore space space straight I space equals space integral subscript 0 superscript straight pi over 2 end superscript fraction numerator sin space straight x over denominator cosx plus sinx end fraction                             ...(2)
Adding (1) and (2), we get.
                 2 straight I space equals space integral subscript 0 superscript straight pi over 2 end superscript open parentheses fraction numerator cos space straight x over denominator sin space straight x space plus space cos space straight x space end fraction plus fraction numerator sin space straight x over denominator sin space straight x plus space cos space straight x end fraction close parentheses dx space equals space integral subscript 0 superscript straight pi over 2 end superscript fraction numerator cosx plus sinx over denominator sinx plus cosx end fraction dx space equals integral subscript 0 superscript straight pi over 2 end superscript 1 space dx

                      equals space open square brackets straight x close square brackets subscript 0 superscript straight pi over 2 end superscript space equals space straight pi over 2 minus 0 space equals space straight pi over 2.

therefore space space space space space space 2 space space straight I space space equals space space straight pi over 2 space space space space space space space space space rightwards double arrow space space space space straight I space equals space straight pi over 4
                      

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 Multiple Choice QuestionsLong Answer Type

162.

Evaluate integral subscript straight pi over 6 end subscript superscript straight pi over 3 end superscript fraction numerator dx over denominator 1 plus square root of tanx end fraction

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163.

Evaluate integral subscript straight pi over 6 end subscript superscript straight pi over 3 end superscript fraction numerator square root of sin space straight x end root over denominator square root of sin space straight x end root plus square root of cos space straight x end root end fraction dx

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 Multiple Choice QuestionsShort Answer Type

164.

Evaluate integral subscript 0 superscript straight pi space sin squared straight x space cos cubed straight x space dx.

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165.

Evaluate integral subscript negative straight pi over 4 end subscript superscript straight pi over 4 end superscript space sin squared straight x space dx

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166.

Evaluate integral subscript negative straight pi over 4 end subscript superscript straight pi over 4 end superscript cos squared xdx

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167.

By using the properties of definite integrals, evaluate
integral subscript negative straight pi over 2 end subscript superscript straight pi over 2 end superscript cosx space dx

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168.

Evaluate integral subscript negative 1 end subscript superscript 1 sin to the power of 5 straight x space cos to the power of 4 straight x space dx

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169.

Evaluate integral subscript negative 1 end subscript superscript 1 space straight x to the power of 17 space cos to the power of 4 straight x space dx.

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170.

Evaluate  integral subscript negative 1 end subscript superscript 1 space log space open parentheses fraction numerator 2 plus straight x over denominator 2 minus straight x end fraction close parentheses dx.

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