Question

Trigonometry question 10c

Answer 1

Check the picture below.

`\cos(\theta )=\cfrac{\stackrel{adjacent}{5}}{\underset{hypotenuse}{11}} \implies \cos^(-1)(~~\cos( \theta )~~) =\cos^(-1)\left( \cfrac{5}{11} \right) \\\\\\ \theta =\cos^(-1)\left( \cfrac{5}{11} \right)\implies \theta \approx 63^o`

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