please help and explain.
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answer : -40/41
steps:
soh cah toa
sin is soh
meaning opposite/hypotenuse
opposite is 9 and
hypotenuse is 41
now you can treat it like a triangle and use the pythagorean theorem
a^2 + 9^2 = 41^2
a^2 + 81 = 1681
a^2 = 1600
a = 40
in soh cah toa
cos is adjacent/hypotenuse so
cos is 40/41
its in quadrant 2 so its negative
-40/41
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