99 Percentile Qs Bank for JEE MainMathematicsTrigonometric Equations
If ^3 + ^3 ( 2 3 + )+ ^3 ( 4 3 + )= 3 , then is equal to
Options
- A1 4
- B3 4
- C5 4
- D7 4
Correct answer
B. 3 4
Step-by-step solution
We have, gathered ^3 + ^3 ( 2 3 + )+ ^3 ( 4 3 + )=a 3 3 +3 4 + 3 ( 2 3 + )+3 ( 2 3 + ) 4 + 3 ( 4 3 + )+3 ( 4 3 + ) 4 =a 3 3 +3 + (2 +3 )+3 ( 2 3 + ) + (4 +3 )+3 ( 4 3 + )=4 a 3 3 +3 + 3 + 3 +3 [ ( 2 3 + ) . 3 3 +3 +3 [2 ( + ) 3 ] gathered gathered =4 a 3 3 3 +3 +3 2 (- ) 1 2 =4 a 3 3 3 +3 -3 =4 a 3 3 3 =4 a 3 a= 3 4 gathered