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22 votes
22 votes
I’m trying to complete old work but this assignment was some time ago and I do not remember the steps to it

I’m trying to complete old work but this assignment was some time ago and I do not-example-1
User Yogi
by
2.7k points

1 Answer

11 votes
11 votes

Given:


\sin\theta=(5)/(13)

Required:

To find the value of


\cos2\theta

Step-by-step explanation:

We know that


\cos2\theta=1-2\sin^2\theta
\begin{gathered} =1-2(\sin\theta)^2 \\ \\ =1-2((5)/(13))^2 \\ \\ =1-2((25)/(169)) \\ \\ =1-(50)/(169) \\ \\ =(169-50)/(169) \\ \\ =(119)/(169) \end{gathered}

Final Answer:


\cos2\theta=(119)/(169)

User MeMyselfAndI
by
3.0k points
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