Question

find the value of: cos 120°.sin150°+sin° 120 .sin150.​

Answer 1

Answer:

Step-by-step explanation:

i think there is an error in the question

it is cos120.sin150+sin120.cos150

if it is so then

sin150=1/2

sin120=√3/2

cos120=  -1/2

cos150=  -√3/2

= -1/2*1/2+√3/2*-√3/2

= -1/4+-3/4

=  -1

if it is not so then

= -1/2*1/2+√3/2*1/2

=  -1/4+√3/4

=(√3-1)/4