Evaluate the function y=cos(sin^-1(x)) geometrically to find the answer in radical form. Set your answer equal to y.
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What is really important here is the equation: \[ \sin^2(x)+\cos^2(x)=1 \]
thats true, i havent studied the trigonometric identities much yet.
We get \[ \sin^2(x) = 1-\cos^2(x) \]
\[\sin(x)\sin(x)=1-\cos(x)\cos(x)\]
We also get \[ \cos^2(x) = 1-\sin^2(x) \]Taking square root of both sides: \[ \cos(x) = \sqrt{1-\sin^2(x)} \] \[ y=\cos(\sin^{-1}(x)) = \sqrt{1-\sin^2(\sin^{-1}(x))} \]Hmmmm.
See what I did there?
so \[y=\cos(\sin ^{-1}(x))\]
eeeeeh, basically what you said. i dun wanna retype it .w. but yes, i think so.
\[ \cos(\color{red}x) = \sqrt{1-\sin^2(\color{red}x)} \\ \cos(\color{red}{\sin^{-1}(x)}) = \sqrt{1-\sin^2(\color{red}{\sin^{-1}(x)})} \]
I hope you are not color blind.
and the whole thins is under the square root because in the original equation the inverse sine of x was the "x"...im not color blind :3
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