हिंदी

lim x → π √ 2 + cos x − 1 ( π − x ) 2 - Mathematics

Advertisements
Advertisements

प्रश्न

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

उत्तर

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

Let x = π  \[-\]h
when x → π, then h → 0

\[= \lim_{h \to 0} \left[ \frac{1 + \cos \left( \pi - h \right)}{\left[ \pi - \left( \pi - h \right) \right]^2 \left[ \sqrt{2 + \cos \left( \pi - h \right)} + 1 \right]} \right]\]
\[ = \lim_{h \to 0} \left[ \frac{1 - \cos h}{h^2 \left[ \sqrt{2 - \cos h} + 1 \right]} \right] \left\{ \because \cos \left( \pi - \theta \right) = - \cos \theta \right\}\]
\[ = \lim_{h \to 0} \left[ \frac{2 \sin^2 \left( \frac{h}{2} \right)}{4 \times \frac{h^2}{4}\left[ \sqrt{2 - \cos h} + 1 \right]} \right]\]
\[ = \frac{1}{2} \lim_{h \to 0} \left[ \left( \frac{\sin \frac{h}{2}}{\frac{h}{2}} \right)^2 \times \frac{1}{\left[ \sqrt{2 - \cos h} + 1 \right]} \right]\]
\[ = \frac{1}{2} \times 1 \times \frac{1}{\left( \sqrt{2 - \cos 0} + 1 \right)}\]
\[ = \frac{1}{2} \times \frac{1}{\left( \sqrt{1} + 1 \right)}\]
\[ = \frac{1}{2 \times 2}\]
\[ = \frac{1}{4}\]

 

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 29: Limits - Exercise 29.9 [पृष्ठ ६५]

APPEARS IN

आरडी शर्मा Mathematics [English] Class 11
अध्याय 29 Limits
Exercise 29.9 | Q 5 | पृष्ठ ६५

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

\[\lim_{x \to 1} \frac{\sqrt{x + 8}}{\sqrt{x}}\] 


\[\lim_{x \to - 1}{\left( 4 x^2 + 2 \right)}\]


\[\lim_{x \to 0} \frac{3x + 1}{x + 3}\] 


\[\lim_{x \to \sqrt{3}} \frac{x^4 - 9}{x^2 + 4\sqrt{3}x - 15}\]


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


\[\lim_{x \to 3} \left( x^2 - 9 \right) \left[ \frac{1}{x + 3} + \frac{1}{x - 3} \right]\] 


\[\lim_{x \to 4} \frac{x^3 - 64}{x^2 - 16}\] 


\[\lim_{x \to 1} \frac{x^{15} - 1}{x^{10} - 1}\] 


\[\lim_{x \to \infty} \sqrt{x^2 + 7x - x}\] 


\[f\left( x \right) = \frac{a x^2 + b}{x^2 + 1}, \lim_{x \to 0} f\left( x \right) = 1\] and \[\lim_{x \to \infty} f\left( x \right) = 1,\]then prove that f(−2) = f(2) = 1


\[\lim_{x \to 0} \frac{\sin x \cos x}{3x}\] 


\[\lim_{x \to 0} \frac{\sin x^n}{x^n}\] 


\[\lim_{x \to 0} \frac{\cos ax - \cos bx}{\cos cx - \cos dx}\] 


\[\lim_{x \to 0} \frac{\sin x^2 \left( 1 - \cos x^2 \right)}{x^6}\] 


\[\lim_{x \to 0} \frac{\tan 3x - 2x}{3x - \sin^2 x}\] 


\[\lim_{x \to 0} \frac{x \tan x}{1 - \cos x}\]


\[\lim_{x \to 0} \frac{3 \sin^2 x - 2 \sin x^2}{3 x^2}\] 


\[\lim_\theta \to 0 \frac{\sin 4\theta}{\tan 3\theta}\] 


\[\lim_{x \to 0} \frac{1 - \cos 5x}{1 - \cos 6x}\]


Evaluate the following limit: 

\[\lim_{h \to 0} \frac{\left( a + h \right)^2 \sin\left( a + h \right) - a^2 \sin a}{h}\] 


\[\lim_{x \to \frac{\pi}{4}} \frac{1 - \tan x}{x - \frac{\pi}{4}}\] 


\[\lim_{x \to \frac{\pi}{4}} \frac{\sqrt{2} - \cos x - \sin x}{\left( \frac{\pi}{4} - x \right)^2}\] 


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


\[\lim_{x \to 1} \frac{1 - x^2}{\sin \pi x}\]


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


\[\lim_{x \to \frac{\pi}{6}} \frac{\cot^2 x - 3}{cosec x - 2}\]


\[\lim_{x \to \frac{\pi}{4}} \frac{\sqrt{2} - \cos x - \sin x}{\left( 4x - \pi \right)^2}\]


Evaluate the following limit:

\[\lim_{x \to \pi} \frac{1 - \sin\frac{x}{2}}{\cos\frac{x}{2}\left( \cos\frac{x}{4} - \sin\frac{x}{4} \right)}\]

 


\[\lim_{x \to \frac{\pi}{4}} \frac{{cosec}^2 x - 2}{\cot x - 1}\]


\[\lim_{x \to 0^+} \left\{ 1 + \tan^2 \sqrt{x} \right\}^{1/2x}\]


\[\lim_{x \to 0} \left( \cos x + \sin x \right)^{1/x}\]


Write the value of \[\lim_{x \to 0^-} \left[ x \right] .\]


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


If \[f\left( x \right) = \left\{ \begin{array}{l}x \sin \frac{1}{x}, & x \neq 0 \\ 0, & x = 0\end{array}, \right.\] then \[\lim_{x \to 0} f\left( x \right)\]  equals 


The value of \[\lim_{x \to 0} \frac{1 - \cos x + 2 \sin x - \sin^3 x - x^2 + 3 x^4}{\tan^3 x - 6 \sin^2 x + x - 5 x^3}\] is 


The value of \[\lim_{n \to \infty} \frac{\left( n + 2 \right)! + \left( n + 1 \right)!}{\left( n + 2 \right)! - \left( n + 1 \right)!}\] is 


Evaluate the following limits: `lim_(x -> 2)[(x^(-3) - 2^(-3))/(x - 2)]`


Evaluate the following Limits: `lim_(x -> "a") ((x + 2)^(5/3) - ("a" + 2)^(5/3))/(x - "a")`


Evaluate the following limits: `lim_(x ->3) [sqrt(x + 6)/x]`


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×