Find the value of θ (0° < θ < 90°) if :

tan 35° cot (90° - θ) = 1.

Given,

tan 35° cot (90° - θ) = 1

We know that,

tan A cot A = 1

∴ 90° - θ = 35°

⇒ θ = 90° - 35°

⇒ θ = 55°.

Hence, θ = 55°.