Step-by-step explanation:
½ [cos(a − b) − cos(a + b)]
Using sum and difference formulas:
½ [cos a cos b + sin a sin b − (cos a cos b − sin a sin b)]
Distribute the negative:
½ (cos a cos b + sin a sin b − cos a cos b + sin a sin b)
Combine like terms:
½ (2 sin a sin b)
Simplify:
sin a sin b
put them together and add them up
Step-by-step explanation:
Every point is translated according to the rule ( x, y ) → ( x + 2, y - 6 )
L ( -1, 2 ) → L´ ( -1 + 2, 2 - 6 ) = ( 1, -4 )