Question

If tan A = | and tan B = Root3
evaluate
i) CosA cos B - sinA sinB
ii) sinA cosB+ cosA cosB

Answer 1

Answer:

i)

Step-by-step explanation:

Tan a = 1

Tan A = tan 45

A = 45.

Now,

Tan b = root 3

Tan b = tan 60.

B = 60.

Now ,

Cos a * cos b - sin A * sin B

= cos 45 * cos 60 - sin 45 * sin 60

= 1/root 2 * 1/2 - 1/root 2 * root 3 /2

= 1 /root 2 ( 1/2 - root 3 /2)

= 1/root 2 * 1 - root 3 /2

= 1 - root 3 / 2 root 2.