Question

Cos 50° cos 60° - Sin 50° Sin60°​

Answer 1

Hi :)

Like i just mentioned we can solve using trig identity

`\tt{cos(a)+cos(b)-sin(a)sin(b)=cos(a+b)}`

Now we can substitute numbers into the formula

`\tt{cos50cos60-sin50sin60}`

Add
`\tt{50}`, and
`\tt{60}`

`\tt{cos(110)}`

Learn more,work harder

Answer 2

cos110°

Explanation:

using the identity

cos(a + b) = cosacosb - sinasinb

then

cos50°cos60° - sin50°cos60°

= cos(50 + 60)°

= cos110°