Question

if tan a=1 and B=root 3 evaluate cosAcosB-sinAsinB

Answer 1

hello users ....
solution:-
we know that
tan 45° = 1
and
tan 60° = √3
and
cos 45° = 1 / √2 
and
cos 60° = 1/2
and
sin 45° = 1 / √2
and
sin 60° = √3 / 2

here,
tan A = 1 = tan 45°
=> A = 45°

and
tan B = √3 = tan 60°
=> B = 60°

And
cos A cos B - sin A sin B

=> cos 45° cos 60° - sin 45°sin 60° 

=> 1 / √2  ×  1 / 2  -  1 / √2 × √3 / 2 

=> 1 / 2√2  - √3 / 2√2

=> (1 - √3) / 2√2  Answer 

# hope it helps :)

Answer 2

Answer:Here is your answer

In the pics