Question

$\cos(45 ) cos(60) - \sin(45) \sin(60)$

Answer 1

Hola there,

cos45° = 1/√2

cos60° = 1/2

sin45° = 1/√2

sin60° = √3/2

So,

=> cos45° cos60° - sin45° sin60°

=> 1/√2×1/2 - 1/√2×√3/2

=> 1/2√2 - √3/2√2

=>(1 - √3)/2√2


Hope this helps...:)

Answer 2

HEYA!!!


HERE IS YOUR ANSWER,

GIVEN : cos(45)cos(60) - sin(45)sin(60)

SOLUTION : 

SINCE,

>> cos(45) = 1/√2 

>> cos(60) = 1/2 

>> sin(45) = 1/√2

>> sin(60) = √3/2 


NOW SUBSTITUTING THE VALUES IN THE EQUATION,

=> (1/√2) × (1/2) - (1/√2) × (√3/2)

=> (1 ÷ 2√2) - (√3 ÷ 2√2)

=> (1 - √3) ÷ (2√2)   (ANS)


HOPE IT HELPS YOU,
THANK YOU.