AP EAMCET202318 May 2023Evening ShiftMathematicsTrigonometric EquationsActual
If 3 ^4 x+2 ^4 x= 6 5 and x is an acute angle, then 2 x =
Options
- A2 6 5
- B2 6
- C3 2 5
- D2 3 5
Correct answer
B. 2 6
Step-by-step solution
aligned & 3 ^4 x+2 ^4 x= 6 5 & 3 ^4 x+2 (1- ^2 x )^2= 6 5 & 3 ^4 x+2 (1+ ^4 x-2 ^2 x )= 6 5 & 25 ^4 x-20 ^2 x+4=0 & ^2 x= 20 400-400 2 25 = 2 5 & ^2 x=1- 2 5 = 3 5 & 2 x=2 2 5 3 5 = 2 5 6 & & 2 x=2 3 5 -1= 1 5 & 2 x=2 6 aligned