हिंदी

Prove that ( 2 √ 3 + 3 ) Sin X + 2 √ 3 Cos X Lies Between − ( 2 √ 3 + √ 15 ) and ( 2 √ 3 + √ 15 )

Advertisements
Advertisements

प्रश्न

Prove that \[\left( 2\sqrt{3} + 3 \right) \sin x + 2\sqrt{3} \cos x\]  lies between \[- \left( 2\sqrt{3} + \sqrt{15} \right) \text{ and } \left( 2\sqrt{3} + \sqrt{15} \right)\]

टिप्पणी लिखिए
Advertisements

उत्तर

\[\text{ Let } f\left( x \right) = (2\sqrt{3} + 3) \sin x + 2\sqrt{3}\cos x\]
\[\text{ We know that }, \]
\[ - \sqrt{\left( 2\sqrt{3} + 3 \right)^2 + \left( 2\sqrt{3} \right)^2} \leq f\left( x \right) \leq \sqrt{\left( 2\sqrt{3} + 3 \right)^2 + \left( 2\sqrt{3} \right)^2}\]
\[ \Rightarrow - \sqrt{12 + 9 + 12\sqrt{3} + 12} \leq f\left( x \right) \leq \sqrt{12 + 9 + 12\sqrt{3} + 12}\]
\[ \Rightarrow - \sqrt{33 + 12\sqrt{3}} \leq f\left( x \right) \leq \sqrt{33 + 12\sqrt{3}}\]
\[\text{ Disclaimer } : \text{ Instead of }- \left( 2\sqrt{3} + \sqrt{15} \right) \text{ and } \left( 2\sqrt{3} + \sqrt{15} \right),\text{ it should be } - \sqrt{33 + 12\sqrt{3}}\text{ and } \sqrt{33 + 12\sqrt{3}} .\]

shaalaa.com
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 7: Values of Trigonometric function at sum or difference of angles - Exercise 7.2 [पृष्ठ २६]

APPEARS IN

आर.डी. शर्मा Mathematics [English] Class 11
अध्याय 7 Values of Trigonometric function at sum or difference of angles
Exercise 7.2 | Q 4 | पृष्ठ २६

वीडियो ट्यूटोरियलVIEW ALL [1]

संबंधित प्रश्न

Prove the following:

sin 2x + 2sin 4x + sin 6x = 4cos2 x sin 4x


Prove the following:

`(cos9x - cos5x)/(sin17x - sin 3x) = - (sin2x)/(cos 10x)`


Prove the following:

`tan 4x = (4tan x(1 - tan^2 x))/(1 - 6tan^2 x + tan^4 x)`


 If \[\sin A = \frac{12}{13}\text{ and } \sin B = \frac{4}{5}\], where \[\frac{\pi}{2}\] < A < π and 0 < B < \[\frac{\pi}{2}\], find the following:
cos (A + B)


If \[\sin A = \frac{3}{5}, \cos B = - \frac{12}{13}\], where A and B both lie in second quadrant, find the value of sin (A + B).


If \[\sin A = \frac{1}{2}, \cos B = \frac{12}{13}\], where \[\frac{\pi}{2}\]< A < π and \[\frac{3\pi}{2}\] < B < 2π, find tan (A − B).


If \[\sin A = \frac{1}{2}, \cos B = \frac{\sqrt{3}}{2}\], where \[\frac{\pi}{2}\] < A < π and 0 < B < \[\frac{\pi}{2}\], find the following:
tan (A + B)


If \[\sin A = \frac{1}{2}, \cos B = \frac{\sqrt{3}}{2}\], where \[\frac{\pi}{2}\] < A < π and 0 < B < \[\frac{\pi}{2}\], find the following:
tan (A - B)


Evaluate the following:
sin 78° cos 18° − cos 78° sin 18°


Evaluate the following:
sin 36° cos 9° + cos 36° sin 9°


 If \[\tan A = \frac{5}{6}\text{ and }\tan B = \frac{1}{11}\], prove that \[A + B = \frac{\pi}{4}\].


Prove that: \[\frac{\sin \left( A + B \right) + \sin \left( A - B \right)}{\cos \left( A + B \right) + \cos \left( A - B \right)} = \tan A\]


Prove that:
\[\frac{\sin \left( A - B \right)}{\cos A \cos B} + \frac{\sin \left( B - C \right)}{\cos B \cos C} + \frac{\sin \left( C - A \right)}{\cos C \cos A} = 0\]

 


Prove that:
sin2 B = sin2 A + sin2 (A − B) − 2 sin A cos B sin (A − B)


Prove that:
cos2 A + cos2 B − 2 cos A cos B cos (A + B) = sin2 (A + B)


Prove that:
tan 36° + tan 9° + tan 36° tan 9° = 1


If x lies in the first quadrant and \[\cos x = \frac{8}{17}\], then prove that:

\[\cos \left( \frac{\pi}{6} + x \right) + \cos \left( \frac{\pi}{4} - x \right) + \cos \left( \frac{2\pi}{3} - x \right) = \left( \frac{\sqrt{3} - 1}{2} + \frac{1}{\sqrt{2}} \right)\frac{23}{17}\]

 


If tan α = x +1, tan β = x − 1, show that 2 cot (α − β) = x2.


Reduce each of the following expressions to the sine and cosine of a single expression: 

24 cos x + 7 sin 


If α + β − γ = π and sin2 α +sin2 β − sin2 γ = λ sin α sin β cos γ, then write the value of λ. 


If a = b \[\cos \frac{2\pi}{3} = c \cos\frac{4\pi}{3}\] then write the value of ab + bc + ca.  


If tan \[\alpha = \frac{1}{1 + 2^{- x}}\] and \[\tan \beta = \frac{1}{1 + 2^{x + 1}}\] then write the value of α + β lying in the interval \[\left( 0, \frac{\pi}{2} \right)\] 


tan 20° + tan 40° + \[\sqrt{3}\] tan 20° tan 40° is equal to 


If \[\cos P = \frac{1}{7}\text{ and }\cos Q = \frac{13}{14}\], where P and Q both are acute angles. Then, the value of P − Q is

 


\[\frac{\cos 10^\circ + \sin 10^\circ}{\cos 10^\circ - \sin 10^\circ} =\]

 


If sin (π cos x) = cos (π sin x), then sin 2x = ______.


The value of cos (36° − A) cos (36° + A) + cos (54° + A) cos (54° − A) is


If tan (π/4 + x) + tan (π/4 − x) = a, then tan2 (π/4 + x) + tan2 (π/4 − x) =


The maximum value of \[\sin^2 \left( \frac{2\pi}{3} + x \right) + \sin^2 \left( \frac{2\pi}{3} - x \right)\] is


If tan 69° + tan 66° − tan 69° tan 66° = 2k, then k =


Express the following as the sum or difference of sines and cosines:

2 sin 3x cos x


If tanθ = `(sinalpha - cosalpha)/(sinalpha + cosalpha)`, then show that sinα + cosα = `sqrt(2)` cosθ.

[Hint: Express tanθ = `tan (alpha - pi/4) theta = alpha - pi/4`]


If cotθ + tanθ = 2cosecθ, then find the general value of θ.


If sinθ + cosecθ = 2, then sin2θ + cosec2θ is equal to ______.


If tanθ = `a/b`, then bcos2θ + asin2θ is equal to ______.


Given x > 0, the values of f(x) = `-3cos sqrt(3 + x + x^2)` lie in the interval ______.


The maximum distance of a point on the graph of the function y = `sqrt(3)` sinx + cosx from x-axis is ______.


State whether the statement is True or False? Also give justification.

If tan(π cosθ) = cot(π sinθ), then `cos(theta - pi/4) = +- 1/(2sqrt(2))`.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×