Question 995591
One way is to find the tangent of 2 sqrt (7);
arc tan of that is 79.30 deg
So the sin of that is 0.9826
The cosine of that is 0.1857
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Another way is those are legs of a right triangle, and squared, they sum to 29 (1+7*4)
the cotangent is adjacent over opposite, so opposite/hypotenuse, or the sine, is 2sqrt (7)/sqrt (29)
That is 0.9826
cosine is 1/sqrt (29)=0.1857