AP EAMCET202422 May 2024Evening ShiftMathematicsTrigonometric EquationsActual
If +4 +9 =0 and +4 +9 =0 , then 81 (2 -2 )-16 (2 -2 )=
Options
- A1+8 ( - )
- B( - )
- C1-36 ( - )
- D1+6 ( - )
Correct answer
A. 1+8 ( - )
Step-by-step solution
From given equations 4 =-( +9 ) ...(i) 4 =-( +9 ) ...(ii) Squaring both sides and adding equations (i) and (ii) aligned & 16 ( ^2 + ^2 )= ( ^2 + ^2 )+81 ( ^2 + ^2 ) & +18( + ) & 16=1+81+18 ( - ) 9 ( - )=-33 & (-33)^2=81 ^2( - ) aligned 1089=81 [1+ (2 -2 ] 2 81 (2 -2 )=2097 ...(iii) From given equations 9 =-( +4 ) ...(iv) 9 =-( +4 ) ...(v) Squaring both sides and adding equations (iv) and (v) aligned & 81 ( ^2 + ^2 )= ( ^2 + ^2 )+16 & ( ^2 + ^2 )+8( + ) & 81=1+16+8 ( - ) ( - )=8 & (2 -2 )=2 ^2( - )-1=127 & Now, 81 (