Which point could be removed in order to make the relation a function? {(–9, –8), (–8, 4), (0, –2), (4, 8), (0, 8), (1, 2)} (0, 8) (4, 8) (1, 2) (–9, –8)

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