Question

sin70 cos20+cos70 sin20=​

Answer 1

Answer:1

Step-by-step explanation:

We know that sin A=cos(90-A)

Therefore

Sin70 cos20+cos70 sin20

=Cos(90-20) cos20+ sin(90-70) sin20

=Cos²20+ sin²20

=1

Since cos²A+sin²A=1

Answer 2

Answer:

0

Step-by-step explanation:

=sin70 cos20 + cos70 sin20

=sin(a-b)cos(a+b)

=sin(70-20)cos(70+20)

=sin50 cos 90

=sin50×0

=0