Question:

Particular integral of $y'' + y = \cosh 3x$ is

Show Hint

For $\cosh ax$ or $\sinh ax$, substitute $D^2 = a^2$. For $\cos ax$ or $\sin ax$, substitute $D^2 = -a^2$.
  • $\frac{1}{10} \cosh 3x$
  • $\frac{-1}{10} \sinh 3x$
  • $3 \cosh x$
  • $x \sinh 3x$
Show Solution
collegedunia
Verified By Collegedunia

The Correct Option is A

Solution and Explanation

Step 1: Concept
For hyperbolic functions like $\cosh ax$, we substitute $D^{2} = a^{2}$ in the operator.

Step 2: Meaning

$P.I. = \frac{1}{D^{2} + 1} \cosh 3x$. Here $a = 3$, so $a^{2} = 9$.

Step 3: Analysis

Substituting $D^{2} = 9$ into the denominator: $\frac{1}{9 + 1} \cosh 3x = \frac{1}{10} \cosh 3x$.

Step 4: Conclusion

Since the denominator is non-zero, this direct substitution yields the particular integral. Final Answer: (A)
Was this answer helpful?
0
0