Practice Questions with Step-by-Step Solutions
Question 1. Evaluate: [\lim_{x→0} \dfrac{(e^{\sin x}-1)}{(\sin x)}]
Step-by-Step Solution:
As [x→0]:
[\sin x → 0]
[e^{\sin x} → 1]
Hence, the limit is of the form [\dfrac{0}{0}].
Let [u = \sin x].
As [x→0], [u→0].
Rewrite the limit:
[\lim_{u→0} \dfrac{(e^{u}-1)}{u}]
Use the standard exponential limit:
[\lim_{u→0} \dfrac{(e^{u}-1)}{u} = 1]
Final Answer:
[1]
Question 2. Evaluate: [\lim_{x→0} \dfrac{(e^{\tan x}-1)}{(\tan x)}]
Step-by-Step Solution:
As [x→0]:
[\tan x → 0]
[e^{\tan x} → 1]
So the form is [\dfrac{0}{0}].
Put [u = \tan x].
As [x→0], [u→0].
Convert the limit:
[\lim_{u→0} \dfrac{(e^{u}-1)}{u}]
Apply the standard result.
Final Answer:
[1]
Question 3. Evaluate: [\lim_{x→0} \dfrac{(e^{2\sin x}-1)}{(\sin x)}]
Step-by-Step Solution:
As [x→0], the form is [\dfrac{0}{0}].
Rewrite:
[\dfrac{e^{2\sin x}-1}{\sin x} ][= 2 \cdot \dfrac{e^{2\sin x}-1}{2\sin x}]
Let [u = 2\sin x].
As [x→0], [u→0].
Apply the standard limit:
[\dfrac{e^{u}-1}{u} → 1]
Multiply:
[2 \cdot 1 = 2]
Final Answer:
[2]
Question 4. Evaluate: [\lim_{x→0} \dfrac{(e^{3\tan x}-1)}{(\tan x)}]
Step-by-Step Solution:
As [x→0], the expression is [\dfrac{0}{0}].
Rewrite:
[\dfrac{e^{3\tan x}-1}{\tan x} ][= 3 \cdot \dfrac{e^{3\tan x}-1}{3\tan x}]
Let [u = 3\tan x], then [u→0].
Apply:
[\dfrac{e^{u}-1}{u} → 1]
Multiply:
[3]
Final Answer:
[3]
Question 5. Evaluate: [\lim_{x→0} \dfrac{(e^{\sin x}-1)}{x}]
Step-by-Step Solution:
As [x→0], numerator and denominator both tend to zero.
Rewrite:
[\dfrac{e^{\sin x}-1}{x} ][= \dfrac{e^{\sin x}-1}{\sin x} \cdot \dfrac{\sin x}{x}]
Apply limits separately:
[\dfrac{e^{\sin x}-1}{\sin x} → 1]
[\dfrac{\sin x}{x} → 1]
Multiply:
[1 \cdot 1 = 1]
Final Answer:
[1]
Question 6. Evaluate: [\lim_{x→0} \dfrac{(e^{\tan x}-1)}{x}]
Step-by-Step Solution:
Rewrite:
[\dfrac{e^{\tan x}-1}{x} ][= \dfrac{e^{\tan x}-1}{\tan x} \cdot \dfrac{\tan x}{x}]
Apply limits:
[\dfrac{e^{\tan x}-1}{\tan x} → 1]
[\dfrac{\tan x}{x} → 1]
Multiply:
[1]
Final Answer:
[1]
Question 7. Evaluate: [\lim_{x→0} \dfrac{(e^{2\sin x}-1)}{x}]
Step-by-Step Solution:
Rewrite carefully:
[\dfrac{e^{2\sin x}-1}{x} ][= 2 \cdot \dfrac{e^{2\sin x}-1}{2\sin x} \cdot \dfrac{\sin x}{x}]
Apply limits:
[\dfrac{e^{2\sin x}-1}{2\sin x} → 1]
[\dfrac{\sin x}{x} → 1]
Multiply:
[2]
Final Answer:
[2]
Question 8. Evaluate: [\lim_{x→0} \dfrac{(e^{5\tan x}-1)}{x}]
Step-by-Step Solution:
Rewrite:
[\dfrac{e^{5\tan x}-1}{x} ][= 5 \cdot \dfrac{e^{5\tan x}-1}{5\tan x} \cdot \dfrac{\tan x}{x}]
Apply limits:
[\dfrac{e^{5\tan x}-1}{5\tan x} → 1]
[\dfrac{\tan x}{x} → 1]
Multiply:
[5]
Final Answer:
[5]
Question 9. Evaluate: [\lim_{x→0} \dfrac{(e^{\sin 2x}-1)}{x}]
Step-by-Step Solution:
Rewrite:
[\dfrac{e^{\sin 2x}-1}{x} ][= \dfrac{e^{\sin 2x}-1}{\sin 2x} \cdot \dfrac{\sin 2x}{2x} \cdot 2]
Apply limits:
[\dfrac{e^{\sin 2x}-1}{\sin 2x} → 1]
[\dfrac{\sin 2x}{2x} → 1]
Multiply:
[2]
Final Answer:
[2]
Question 10. Evaluate: [\lim_{x→0} \dfrac{(e^{\tan 3x}-1)}{x}]
Step-by-Step Solution:
Rewrite:
[\dfrac{e^{\tan 3x}-1}{x} ][= \dfrac{e^{\tan 3x}-1}{\tan 3x} \cdot \dfrac{\tan 3x}{3x} \cdot 3]
Apply limits:
[\dfrac{e^{\tan 3x}-1}{\tan 3x} → 1]
[\dfrac{\tan 3x}{3x} → 1]
Multiply:
[3]
Final Answer:
[3]