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Question
If `cos theta = 2/3 , " write the value of" (4+4 tan^2 theta).`
Solution
`4+4 tan^2 theta `
= `4(1+ tan ^2 theta)`
=`4 sec^2 theta `
=`4/ cos^2 theta`
=`4/(2/3)^2`
=`4/((4/9))`
=`(4xx9)/4`
=9
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