हिंदी

Lim X → 0 E X − 1 √ 1 − Cos X

Advertisements
Advertisements

प्रश्न

\[\lim_{x \to 0} \frac{e^x - 1}{\sqrt{1 - \cos x}}\]

Advertisements

उत्तर

\[\lim_{x \to 0} \left[ \frac{e^x - 1}{\sqrt{1 - \cos x}} \right]\]
\[\text{ Rationalising the denominator, we get }: \]
\[ = \lim_{x \to 0} \left[ \frac{\left( e^x - 1 \right)}{\sqrt{1 - \cos x}} \times \frac{\sqrt{1 + \cos x}}{\sqrt{1 + \cos x}} \right]\]
\[ = \lim_{x \to 0} \left[ \frac{\left( e^x - 1 \right) \left( \sqrt{1 + \cos x} \right)}{\sqrt{1 - \cos^2 x}} \right]\]
\[ = \lim_{x \to 0} \left[ \frac{\left( e^x - 1 \right) \sqrt{1 + \cos x}}{\left| \sin x \right|} \right]\]

Dividing numerator and the denominator by x, we get:

\[= \lim_{x \to 0} \left[ \left( \frac{e^x - 1}{x} \right) \times \frac{\sqrt{1 + \cos x}}{\left( \frac{\left| \sin x \right|}{x} \right)} \right]\]
\[\text{ Left hand limit }: \]
\[ \lim_{x \to 0^-} \left[ \left( \frac{e^x - 1}{x} \right) \times \frac{\sqrt{1 + \cos x}}{\left( \frac{\left| \sin x \right|}{x} \right)} \right]\]
\[ = \lim_{x \to 0^-} \left[ \left( \frac{e^x - 1}{x} \right) \times \frac{\sqrt{1 + \cos x}}{\left( \frac{- \sin x}{x} \right)} \right]\]
\[ = - \frac{1 \times \sqrt{2}}{1}\]
\[ = - \sqrt{2}\]
\[\text{ Right hand limit }: \]
\[ \lim_{x \to 0^+} \left[ \left( \frac{e^x - 1}{x} \right) \times \frac{\sqrt{1 + \cos x}}{\frac{\left| \sin x \right|}{x}} \right]\]
\[ = \lim_{x \to 0^+} \left[ \left( \frac{e^x - 1}{x} \right) \times \frac{\sqrt{1 + \cos x}}{\frac{\sin x}{x}} \right]\]
\[ = 1 \times \frac{\sqrt{2}}{1}\]
\[ = \sqrt{2}\]

Left hand limit ≠ Right hand limit
Thus, limit does not exist.

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 29: Limits - Exercise 29.1 [पृष्ठ ७१]

APPEARS IN

आर.डी. शर्मा Mathematics [English] Class 11
अध्याय 29 Limits
Exercise 29.1 | Q 29 | पृष्ठ ७१

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

Find `lim_(x -> 0)` f(x), where `f(x) = {(x/|x|, x != 0),(0, x = 0):}`


If f(x) = `{(|x| +  1,x < 0), (0, x = 0),(|x| -1, x > 0):}`

For what value (s) of a does `lim_(x -> a)`  f(x) exists?


if `f(x) = { (mx^2 + n, x < 0),(nx + m, 0<= x <= 1),(nx^3 + m, x > 1):}`

For what integers m and n does `lim_(x-> 0) f(x)` and `lim_(x -> 1) f(x)` exist?


\[\lim_{x \to 0} \frac{\sqrt{1 + x + x^2} - 1}{x}\]


\[\lim_{x \to 0} \frac{\sqrt{1 + x} - \sqrt{1 - x}}{2x}\]


\[\lim_{x \to 0} \frac{x}{\sqrt{1 + x} - \sqrt{1 - x}}\] 


\[\lim_{x \to 1} \frac{\sqrt{5x - 4} - \sqrt{x}}{x - 1}\] 


\[\lim_{x \to 1} \frac{x - 1}{\sqrt{x^2 + 3 - 2}}\] 


\[\lim_{x \to 1} \frac{\sqrt{5x - 4} - \sqrt{x}}{x^2 - 1}\] 


\[\lim_{x \to 5} \frac{x - 5}{\sqrt{6x - 5} - \sqrt{4x + 5}}\] 


\[\lim_{x \to 2} \frac{\sqrt{1 + 4x} - \sqrt{5 + 2x}}{x - 2}\] 


\[\lim_{x \to 1} \frac{\sqrt{3 + x} - \sqrt{5 - x}}{x^2 - 1}\] 


\[\lim_{x \to 0} \frac{\sqrt{1 + x + x^2} - \sqrt{x + 1}}{2 x^2}\] 


\[\lim_{h \to 0} \frac{\sqrt{x + h} - \sqrt{x}}{h}, x \neq 0\] 


\[\lim_{x \to \sqrt{10}} \frac{\sqrt{7 + 2x} - \left( \sqrt{5} + \sqrt{2} \right)}{x^2 - 10}\] 


\[\lim_{x \to \sqrt{6}} \frac{\sqrt{5 + 2x} - \left( \sqrt{3} + \sqrt{2} \right)}{x^2 - 6}\] 

 


\[\lim_{x \to \sqrt{2}} \frac{\sqrt{3 + 2x} - \left( \sqrt{2} + 1 \right)}{x^2 - 2}\] 


\[\lim_{x \to 0} \frac{a^x + b^x - 2}{x}\]


\[\lim_{x \to 0} \frac{a^{mx} - b^{nx}}{x}\] 


\[\lim_{x \to 0} \frac{a^x + b^x + c^x - 3}{x}\] 


\[\lim_{x \to 2} \frac{x - 2}{\log_a \left( x - 1 \right)}\]


\[\lim_{x \to \infty} \left( a^{1/x} - 1 \right)x\]


\[\lim_{x \to 0} \frac{a^{mx} - b^{nx}}{\sin kx}\]


\[\lim_{x \to 0} \frac{e^x - 1 + \sin x}{x}\]


\[\lim_{x \to 0} \frac{e\sin x - 1}{x}\] 


\[\lim_{x \to a} \frac{\log x - \log a}{x - a}\] 


\[\lim_{x \to 0} \frac{\sqrt{1 + x} - 1}{\log \left( 1 + x \right)}\] 


\[\lim_{x \to 0} \frac{e^{bx} - e^{ax}}{x} \text{ where } 0 < a < b\] 


\[\lim_{x \to 0} \frac{x\left( e^x - 1 \right)}{1 - \cos x}\]


\[\lim_{x \to 1} \left\{ \frac{x^3 + 2 x^2 + x + 1}{x^2 + 2x + 3} \right\}^\frac{1 - \cos \left( x - 1 \right)}{\left( x - 1 \right)^2}\]


\[\lim_{x \to 0} \left\{ \frac{e^x + e^{- x} - 2}{x^2} \right\}^{1/ x^2}\]


\[\lim_{x \to 0} \frac{\sin x}{\sqrt{1 + x} - 1} .\] 


Evaluate: `lim_(h -> 0) (sqrt(x + h) - sqrt(x))/h`


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×