Question

In triangle $ghi$, we have $gh = hi = 25$ and $gi = 30$. what is $\sin\angle ghi$? (note: this is not the exact same as the previous problem!)

Answer 1

We have the following rule:

`cos (ghi)= (gh^2+ih^2-gi^2)/(2(gh)(ih))\\= (25^2+25^2-30^2)/(2*25*25)=0.28`
In order to find the sine, simply do like this:

`sin(ghi)=√(1-0.28^2)=0.96`