Question
Differentiate the following from first principle

$\text{a}^{\sqrt{\text{x}}}$

Answer

$\text{f}(\text{x})=\text{a}^\sqrt{\text{x}}=\text{e}^{\sqrt{\text{x}}\log\text{a}}$

$\text{f}'(\text{x})=\lim_\limits{\text{h}\rightarrow0}\frac{\text{f}(\text{x}+\text{h})-\text{f}(\text{x})}{\text{h}}$

$=\lim_\limits{\text{h}\rightarrow0}\frac{\text{e}^{\sqrt{\text{x}+\text{h}}\log\text{a}}-\text{e}^{\sqrt{\text{x}}\log\text{a}-1}}{\text{h}}$

$=\lim_\limits{\text{h}\rightarrow0}\text{e}^{\sqrt{\text{x}}\log\text{a}}\frac{\text{e}^{\sqrt{\text{x}+\text{h}}\log\text{a}-\sqrt{\text{x}}\log\text{a}}-1}{\text{h}}$

$=\lim_\limits{\text{h}\rightarrow0}\text{e}^{\sqrt{\text{x}}\log\text{a}}\frac{\text{e}^{(\sqrt{\text{x}+\text{h}}-\sqrt{\text{x}})\log\text{a}}-1}{\text{h}}$

Multiply numerator and denominator by $(\sqrt{\text{x}+\text{h}}-\sqrt{\text{x}})\log\text{a}$

$\text{f}(\text{x})=\lim_\limits{\text{h}\rightarrow0}\text{e}^{\sqrt{\text{x}}\log\text{a}}\frac{\text{e}^{(\sqrt{\text{x}+\text{h}}-\sqrt{\text{x}})\log\text{a}}-1}{\text{h}(\sqrt{\text{x}+\text{h}}-\sqrt{\text{x}})\log\text{a}}(\sqrt{\text{x}+\text{h}}-\sqrt{\text{x}})\log\text{a}$

$=\text{e}^{\sqrt{\text{x}}\log\text{a}}\lim_\limits{\text{h}\rightarrow0}\frac{\text{e}^{(\sqrt{\text{x}+\text{h}}-\sqrt{\text{x}})\log\text{a}}-1}{(\sqrt{\text{x}+\text{h}}-\sqrt{\text{x}})\log\text{a}}\lim_\limits{\text{h}\rightarrow0}\log\text{a}\frac{(\sqrt{\text{x}+\text{h}}-\sqrt{\text{x}})}{\text{h}}$

$=\text{e}^{\sqrt{\text{x}}\log\text{a}}\lim_\limits{\text{h}\rightarrow0}\log\text{a}\frac{(\sqrt{\text{x}+\text{h}}-\sqrt{\text{x}})}{\text{h}}$

Multiply numerator and denominator by $(\sqrt{\text{x}+\text{h}}-\sqrt{\text{x}})$

$\text{f}(\text{x})=\text{e}^{\sqrt{\text{x}}\log\text{a}}\lim_\limits{\text{h}\rightarrow0}\log\text{a}\frac{(\sqrt{\text{x}+\text{h}}-\sqrt{\text{x}})}{\text{h}(\sqrt{\text{x}+\text{h}}-\sqrt{\text{x}})}(\sqrt{\text{x}+\text{h}}-\sqrt{\text{x}})$

$=\text{e}^{\sqrt{\text{x}}\log\text{a}}\lim_\limits{\text{h}\rightarrow0}\log\text{a}\frac{\text{h}}{\text{h}(\sqrt{\text{x}+\text{h}}-\sqrt{\text{x}})}$

$=\text{e}^{\sqrt{\text{x}}\log\text{a}}\frac{\log\text{a}}{2\sqrt{\text{x}}}$

$=\frac{\text{a}^{\sqrt{\text{x}}}}{2\sqrt{\text{x}}}\log_\text{e}\text{a}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

$\text{a}^2=(\text{b + c})^2-4\text{bc}\cos^2\frac{\text{A}}{2}$
Find the vertex, focus, axis, directrix and latus-rectum of the following parabolas:
y2 = 5x - 4y - 9.
An experiment involves rolling a pair of dice and recording the numbers that come up. Describe the following events:
A: the sum is greater than 8, B: 2 occurs on either die.
C: the sum is at least 7 and a multiple of 3
which pairs of these events are mutually exclusive?
If $\sin\text{x}+\cos\text{x}=0$ and x lies in the fourth quadrant, find $\sin \text{x } $and $\cos\text{x}.$
To receive grade 'A' in a course, one must obtain an average of 90 marks or more in five papers each of 100 marks. If Shikha scored 87, 95, 92 and 94 marks in first four paper, find the minimum marks that she must score in the last paper to get grade 'A' in the course.
A visitor with sign board 'DO NOT LITTER' is moving on a circular path in an exhibition. During the movement he stops at points represented by (3, - 2) and (-2, 0). Also, centre of the circular path is on the line 2x - y = 3. What is the equation of the path? What message he wants to give to the public?
Reduce each of the following expressions to the sine and cosin of a single expression:
$\sqrt{3}\sin\text{x}-\cos\text{x}$
Find the mean deviation from the mean for following data:
xi
5
10
15
20
25
fi
7
4
6
3
5
Find the angles between the following pairs of straight lines:
3x - y + 5 = 0 and x - 3y + 1 = 0
Prove the following statement by principle of mathematical induction:
23n - 1 is divisible by 7, for all natural numbers n.