Question

of tan A=1 and tan B=root 3, evaluate
i) CosACosB-Sin A Sin B
ii) SinACosB +CosA Sin B
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Answer 1

Answer:

Step-by-step explanation:

i) Tan a = 1

Tan A = tan 45

A = 45.

Now,

TanB = √3

TanB = tan 60.

B = 60.

Now ,

CosA * cosB - sin A * sin B

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

= 1/√2 * 1/2 - 1/√2 *√3 /2

= 1 /√2 ( 1/2 - √3 /2)

= 1/√2 * 1 - √3 /2

= 1 - √3 / 2 √2.