NDA2019MathematicsTrigonometric Ratios & IdentitiesActual
What is 25^ 15^ + 15^ 50^ + 25^ 50^ equal to?
Options
- A0
- B1
- C2
- D4
Correct answer
B. 1
Step-by-step solution
aligned & 25^ 15^ + 15^ 50^ + 50^ 25^ & = 15^ ( 15^ + 50^ )+ 50^ 25^ & (1) & 75^ = 25^ + 50^ 1- 25^ 50^ = 15^ & 25^ + 50^ = 15^ (1- 25^ 50^ ) & Put in (1) & 15^ 15^ (1- 25^ 50^ ) & =1- 25^ 50^ + 50^ 25^ + 50^ 25^ & =1 aligned