Let ABC be a right-angled triangle where ∠A = 90° and ∠C= 45°. Find the value of sec C + sin C sec C.
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 1 + .
In triangle ABC, ∠A = 90°, ∠C = 45°
⇒ ∠B = 45° (since sum of angles in triangle = 180°)
Let the sides opposite 45° angles be 1 unit each, then hypotenuse = √2
So, for ∠C = 45°:
sec C = hypotenuse / adjacent = √2 / 1 = √2
sin C = opposite / hypotenuse = 1 / √2
Now:
sec C + sin C × sec C = √2 + (1/√2)(√2) = √2 + 1