Question

(a) sin 10° cos 80° + cos 10° sin 80°

solve it ...(without using table )​

Answer 1

Answer:

sin 10°cos80°+cos10°sin80°

It is of the form sin (x+y) = sinxcosy+cosxsiny

•°• sin 10°cos80°+cos10°sin80° = sin(10+80)

= sin90° = 1

sin 10°cos80°+cos10°sin80° = 1

PLZ MARK AS BRAINLIEST !

Answer 2

Concept

Recall the formula which use to solve the question

sin² x+ cos² x=1

Given

The problem sin 10° cos 80° + cos 10° sin 80

To find

We have to solve this problem.

Solution

Rewrite the problem to simplify

sin 10° cos (90-10)° + cos 10° sin (90-10)°

We know sin (90-x)° = cos (90-x)° and cos (90-x)° = sin (90-x)°

then,

sin 10° sin 10° + cos 10° cos 10°=  sin² 10°+ cos² 10°

                                                 =1

Hence 1 is the final answer.