AP EAMCET202422 May 2024Evening ShiftMathematicsApplication of DerivativesActual
If the curves 2 x^2+k y^2=30 and 3 y^2=28 x cut each other orthogonally, then k=
Options
- A5
- B3
- C2
- D1
Correct answer
D. 1
Step-by-step solution
2 x^2+k y^2=30 ...(i) 4 x+2 k y d y d x =0 d y d x = -2 x k y =m₁ And 3 y^2=28 x ...(ii) 6 y d y d x =28 d y d x = 14 3 y =m₂ Since, curves cut orthogonally aligned & m₁ m₂=-1 -2 x k y 14 3 y =-1 & k= 28 x 3 y^2 =1 aligned [From (ii)]