Question

(sin 70°+ cos 20°) (cos20°- sin70°)=​

Answer 1

Answer:

0

Step-by-step explanation:

sin70=sin(90-20)=cos20

sin70+cos20 )(cos20-cos20)

=(sin70+cos20)(0)

=0

Answer 2

Answer:

sin20° cos70° + sin70° cos20° = cos(90° – 20°)cos70° + sin70° sin(90° – 20°) = cos 70° cos70° + sin70° sin70° = cos270° + sin270° = 1Read more on Sarthaks.com - https://www.sarthaks.com/649207/the-value-of-sin20-cos70-sin70-cos20-is?show=649217#a649217