Question

V 2
sin330° cos 120° + cos2100.sin 300º =
a) 1
b)1/2
c)root3/2
d) 0
​

Answer 1

Answer:

Step-by-step explanation:

Alternatively we may write as follows----

                        sin330= -sin30 = -(1/2)

                        cos120=-cos60 = -(1/2)

                        cos210= -cos30 =(-√(3)/2)

                         sin300=-sin60 = (-√(3)/2)

Putting these values in below equation, we get---------

sin 330.cos 120+cos 210.sin 300

=(-1/2)(-1/2) + (-√(3)/2)(-√(3)/2)

= 1/4+3/4

=1