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Question
If 5 `tan theta = 4,"write the value of" ((cos theta - sintheta))/(( cos theta + sin theta))`
Solution
We have ,
5 `tan theta = 4`
⇒ `tan theta = 4/5`
Now ,
`((cos theta - sintheta))/(( cos theta + sin theta))`
`=(((cos theta )/(cos theta)- (sin theta )/(cos theta)))/((cos theta/ cos theta+ sin theta/ cos theta)` (๐ท๐๐ฃ๐๐๐๐๐ ๐๐ข๐๐๐๐๐ก๐๐ ๐๐๐ ๐๐๐๐๐๐๐๐๐ก๐๐ ๐๐ฆ cos θ)
`=((1- tan theta))/((1+ tan theta))`
`= ((1/1-4/5))/((1/1+4/5))`
`= ((1/5))/((9/5))`
`= 1/9`
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