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Question
If `cos theta = 2/3 , "write the value of" ((sec theta -1))/((sec theta +1))`
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Solution
`(sec theta -1)/( sec theta +1)`
= `((1/cos theta - 1/1))/((1/ costheta + 1/1))`
=`(((1- cos theta)/cos theta))/(((1+ cos theta)/cos theta))`
=`(1- cos theta)/(1+ cos theta)`
=`((1/1-2/3))/((1/1+2/3)`
=`((1/3))/((5/3))`
=`1/5`
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