1.

sin-1 x + cos-1 x=?

1-    π/4

2-    π

3-    π/2

4-    2π

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2.

If,

-π/2 < Ө < π/2

Sinhx= tgӨ

Then,

Coshx=?

1-    cos Ө

2-    csc Ө

3-    sec Ө

4-    sin Ө

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3.

2 Arctg (1/2)=?

1-    Arctg (4/3)

2-    Arctg (3/4)

3-    Arctg (2/3)

4-    Arctg (3/2)