trig problem

What is sin GIH?  What is sin GHI?

Hello Guest!

law of cosines:

$a^2= c^2+b^2-2bc\cdot cos\ \alpha\\ \color{blue}sin\ \alpha=sin\ (arc cos\ \dfrac{c^2+b^2-a^2}{2bc})$

You can calculate it yourself.

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What is sin GIH?  What is sin GHI?

$sin\ GIH=sin \ arccos\ \frac{9}{10}=sin\ 25.842°=\color{blue}0.43589\\ sin\ GHI=sin\ (180-2\cdot 25.842)°=sin\ 128.316°=\color{blue}0.7846$

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