Find the requested function value of θ. If sin θ = 4 over 13, find cos θ
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draw a triangle! sin θ = 4/13 so opposite is 4 and hypotenuse is 13. just rearrange pythagoras theorem.
ok i did 13^2 and 4^ 2
i got 169 and 16
do i subtract them from eachother to get 153?
the answer is supposed to be square root of 153 over 13
a² + b² = c²
b => +(c²-a²)^0.5
Note: square rooting gives ±, obviously length is not - so we take the + one.
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