AP EAMCET202318 May 2023Morning ShiftMathematicsTrigonometric EquationsActual
_ k=0 ^4 ^2(2 k+1) 20 =
Options
- A5
- B5 2
- C3
- D3 2
Correct answer
B. 5 2
Step-by-step solution
_ k=0 ^4 ^2(2 k+1) 20 aligned & = ^2 20 + ^2 3 20 + ^2 5 20 + ^2 7 20 + ^2 9 20 & = ^2 ( 2 - 9 20 )+ ^2 ( 2 - 7 20 ) aligned + ^2 5 20 + ^2 7 20 + ^2 9 20 = ^2 ( 9 20 )+ ^2 ( 7 20 )+ ^2 5 20 + ^2 7 20 + ^2 5 20 =1+1+ ^2 4 =1+1+ 1 2 = 5 2