Choose the correct equation for the function shown in the graph. y = sinx y = cosx y = cos 2x y = -sin 2x

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Consider that lines b and c are parallel. what is the value of x? what is the measure of the smaller angle?

Which sum or difference identity would you use to verify that cos (180° - q) = -cos q? a.) sin (a -b) = sin a cos b – cos a sin b b.) cos (a -b) = cos a cos b – sin a sin b c.) cos (a -b) = cos a cosb + sin a sin b d.) sin (a + b) = sin a cos b + cos a sin b