Question

Prove that Sec70º Sin 20° +Cosec 70°Сos20°=2​

Answer 1

Answer:

Consider (sec 70° sin 20°) + (cos 20° cosec 70°)

= (sec (90 – 20)° sin 20°) + (cos 20° cosec (90 – 20)°)

= (cosec 70° sin70°) + (cos 20° sec 20°)

= 1 + 1 (∵ cosec θ = 1/sin θ and sec θ = 1/cos θ )

= 2

Answer 2

Step-by-step explanation:

consider (sec 70° sin 20°)+(cos 20° cosec70°)

=(sec(90°-20°)sin20°)+(cos20°cosec(90°-20°)

(cosec70° sin70°) +(cos20°sec20°)

=1+1(:•cosec0=1(sin0 and sec0 =1/cos0)

=2