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Question
If sin θ =7/25, where θ is an acute angle, find the value of cos θ.
Solution
`sintheta=7/25`
we know `sin theta="Opposite"/"Hypotunes"=p/h`
`therefore p/h=7/25` [∵ Opposite = Perpendicular = p]
p=7k, h=25k
Let the adjacent (base) side be b.
Thus `b=sqrt((25k)^2-(7k)^2)=24k`
`costheta=(24k)/(25k)=24/25`
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