NIMCET 2021 — Mathematics PYQ
NIMCET | Mathematics | 2021The integral ∫ex(sinhx+coshx)dx is equal to:
Choose the correct answer:
- A.
exsechx+c
- B.
excoshx+C
(Correct Answer) - C.
sinh2x+C
excoshx+C
Explanation
Step 1: Use the definitions of sinhx and coshx.
The hyperbolic sine and cosine functions are defined as:
Step 2: Add the two functions.
Step 3: Substitute the simplified expression into the integral.
The integral becomes:
Step 4: Integrate with respect to x.
Using the rule ∫eaxdx=aeax+C:
Alternative Method (Using ex[f(x)+f′(x)] property):
Let f(x)=sinhx, then f′(x)=coshx.
We know that ∫ex[f(x)+f′(x)]dx=exf(x)+C.
Substituting sinhx=2ex−e−x:
Since 2−1 is a constant, it can be absorbed into the constant of integration C:
Final Answer:
Explanation
Step 1: Use the definitions of sinhx and coshx.
The hyperbolic sine and cosine functions are defined as:
Step 2: Add the two functions.
Step 3: Substitute the simplified expression into the integral.
The integral becomes:
Step 4: Integrate with respect to x.
Using the rule ∫eaxdx=aeax+C:
Alternative Method (Using ex[f(x)+f′(x)] property):
Let f(x)=sinhx, then f′(x)=coshx.
We know that ∫ex[f(x)+f′(x)]dx=exf(x)+C.
Substituting sinhx=2ex−e−x:
Since 2−1 is a constant, it can be absorbed into the constant of integration C:
Final Answer:

