AP EAMCET2004MathematicsTrigonometric Equations
The expression 9^ - 27^ - 63^ + 81^ is equal to
Options
- A4
- B3
- C2
- D1
Correct answer
A. 4
Step-by-step solution
aligned & 9^ - 27^ - 27^ + 9^ & = ( 9^ 9^ + 9^ 9^ )- ( 27^ 27^ + 27^ 27^ ) & = ( ^2 9^ + ^2 9^ 9^ )- ( ^2 27^ + ^2 27^ 27^ 27^ ) & = 2 18^ - 2 54^ & = 2 5 -1 4 - 2 5 +1 4 = 8 5 -1 - 8 5 +1 & = 16 5-1 = 16 4 =4 aligned