Question

Consider the following statement

(1) Sin2A + 2(Sin A Cosec A) + Cos²A = 3

(2) [Sec(90° – A) Tan(90° – A)/Cot A] – Cosec A = 0

(3) Sin2° Sin20° Sin45° (1/Cos70°) (1/Cos88°) = 1/√2

Which of the following statement is/are correct?

1.

1, 2 and 3

2. Only 3
3. Only 1
4. Only 2

Answer 1

Correct Answer - Option 1 :

1, 2 and 3

Statement 1

 [(1/Cosec A) × Cosec A]2 + 1

⇒  1× 2 + 1

⇒  3

Statement 2

 [(Cosec A Cot A)/Cot A] – Cosec A

⇒  Cosec A – Cosec A

⇒  0

Statement 3

Sin(90° – 88°) Sin(90° – 70°) (1/√2) (1/Cos 70°) (1/Cos 88°)

⇒  Cos 88°Cos 70 °(1/√2) (1/Cos 70°) (1/Cos 88°)

⇒  1/√2

Each statement is correct