NDA2010MathematicsTrigonometric Ratios & IdentitiesActual
What is the value of 15^ + 45^ ^3 15^ + ^3 45^ ?
Options
- A1 4
- B1 2
- C1 3
- DNone of these
Correct answer
D. None of these
Step-by-step solution
aligned & 15^ + 45^ ( 15^ )^3+ ( 45^ )^3 = & (45^ -30^ ) = & 45^ 30^ + 45^ 30^ = & 1 2 3 2 + 1 2 1 2 = 3 +1 2 2 = & 1 ( 3 +1 2 2 )^2+ ( 1 2 )^2- 3 +1 2 2 1 2 = & 1 3+1+2 3 +4-2 3 -2 8 = 8 -2 =-4 aligned