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Question
If `cot theta = 1/ sqrt(3) , "write the value of" ((1- cos^2 theta))/((2 -sin^2 theta))`
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Solution
We have ,
`cot theta = 1/ sqrt(3)`
⇒` cot theta = cot (π/3)`
⇒`theta = π/3`
Now ,
`((1- cos^2 theta))/((2 - sin^2 theta))`
= `(1- cos ^2(π/3))/( 2 - sin ^2 ( π/ 3))`
=` (1- (1/2)^2)/(2-(sqrt(3)/2)^2)`
=` ((1/1 - 1/4))/((2/1-3/4))`
=`((3/4))/((5/4))`
=`3/5`
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Activity:
L.H.S = `square`
= `square/sintheta + sintheta/costheta`
= `(cos^2theta + sin^2theta)/square`
= `1/(sintheta*costheta)` ......`[cos^2theta + sin^2theta = square]`
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= R.H.S
