Q79.If 2x = y 15 + y−15 and (x2 −1) dx2d2y + λx dxdy + ky = 0 (1) 26 (2) −24 (3) −23 (4) −26
What This Question Tests
This question tests the ability to derive a second-order linear differential equation from a given implicit function relating x and y, and then identify the coefficients by comparing it with the given differential equation. The standard derivation yields k = -25, which is not among the options. Assuming there might be a typo in the options or question, option (4) -26 is the closest integer.
Concepts Tested
Formulas Used
d/dx(f(y)) = f'(y)dy/dx
d/dx(uv) = u'v + uv'
(x^2-1)y'' + xy' - m^2y = 0 for y=(x+sqrt(x^2-1))^m
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📋 Question Details
- Chapter
- Differential Equations
- Topic
- Higher order linear differential equations
- Year
- 2017
- Shift
- 09 Apr Online
- Q Number
- Q79
- Type
- MCQ
- NCERT Ref
- Class 12 Mathematics Ch 9: Differential Equations
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