Q7 of 186 Page 345

Write the value of sin θ cos (90° – θ) + cos θ sin (90° – θ).

Consider sin θ cos (90° – θ) + cos θ sin (90° – θ) = sin θ sin θ + cos θ cos θ

= sin² θ + cos² θ

(∵ sin² θ + cos² θ = 1)

= 1

Write the value of .

Write the value of cosec² (90° – θ) – tan² θ.

Write the value of sec² θ (1 + sin θ)(1 – sin θ).