Prove the sinθ sin (90° – θ) – cos θ cos (90° – θ) = 0

Prove that sin 48° sec 48° + cos 48° cosec 42° = 2

Prove that tan 20° tan 35° tan 45° tan 55° tan 70° = 1

Evaluate the \( 2sin 3x = \sqrt{3}\)

Evalute the following:

(i) \( \dfrac{sin 20°}{ cos 70°}\)

(ii) \(\dfrac{ cos 19°}{ sin 71°}\)

(iii) \( \dfrac{sin 21°}{ cos 69°}\)

(iv) \( \dfrac{tan 10°}{ cot 80°}\)

(v) \( \dfrac{sec 11°}{ cosec 79°}\)