Welke gelijkheid is correct ?
A.   sin (270° + α) = sin (270° – α)
B.   cos (270° + α) = cos (270° – α)
C.   tan (270° + α) = tan (270° – α)
D.   cot (270° + α) = cot (270° – α)
E.   geen van de vorige vier is juist
    A    B    C    D    E

[ 4-5876 - op net sinds 15.9.2025-(E)- ]

Translation in   E N G L I S H

IN CONSTRUCTION

Oplossing - Solution

sin (270° + α) = sin (−90° + α) = − sin (90° − α) = − cos α
sin (270° – α) = sin (−90° − α) = − sin (90° + α) = − cos (−α) = − cos α
GWB