Mathematics: If sin theta 3/5 and theta terminates in the first quadrant find the exact value of cos 2 theta

4x4 gives you 16 and plus 153 equals 169...

If sin theta 3/5 and theta terminates in the first

xojade

04.01.2022

$cos2\theta =\frac{7}{25}$

Step-by-step explanation:

We have

$sin\theta =\frac{3}{5}$

We know

sin²θ + cos²θ = 1

$\left (\frac{3}{5} \right )^2+cos^2\theta =1\\\\cos^2\theta =\frac{16}{25}\\\\cos\theta =\frac{4}{5}$

We need to find cos2θ

We have

cos2θ = cos²θ - sin²θ

$cos2\theta =\left (\frac{4}{5} \right )^2-\left (\frac{3}{5}\right )^2=\frac{7}{25}$

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