Question

please give solution ​

Answer 1

Answer:

Sin A = 1/2

Sin A = Sin 30°

Now,

A = 30° ----(1)

Cos B = 1 /2

Cos B = Cos 60°

B = 60° ----(2)

Now,

Value of (A + B) = 30° + 60° [ from (1)&(2) ]

= 90°

Therefore,. A + B = 90°

Answer 2

Answer:

7. (d)

8.(d)

9.(a)

Step-by-step explanation:

7.Given Sin A = 1 /2

12 Sin A = Sin 30°

Now, A = 30° ----(1) Cos B = 1 /2

12 Cos B = Cos 60° B = 60° ----(2)

Now, Value of (A + B) = 30° + 60° [ from (1)&(2) ] = 90° Therefore,. A + B = 90°

8. Tan theta is not defined when theta is equal to 90°

9. Since cosec theta is the reciprocal of sin theta, so it is undefined wherever sin theta is 0.