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Let f(x)=(sin 2n x)/(1+cos^(2)nx), n in ...

Let `f(x)=(sin 2n x)/(1+cos^(2)nx), n in N ` has `(pi)/(6)` as its fundamental period , then n=

A

2

B

4

C

6

D

none of these

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The correct Answer is:
To solve the problem, we need to find the value of \( n \) such that the function \[ f(x) = \frac{\sin(2nx)}{1 + \cos^2(nx)} \] has a fundamental period of \( \frac{\pi}{6} \). ### Step 1: Determine the period of the numerator The numerator of the function is \( \sin(2nx) \). The period of \( \sin(kx) \) is given by \[ \frac{2\pi}{k}. \] For \( \sin(2nx) \), we have \( k = 2n \), so the period \( P_1 \) is: \[ P_1 = \frac{2\pi}{2n} = \frac{\pi}{n}. \] ### Step 2: Determine the period of the denominator The denominator is \( 1 + \cos^2(nx) \). The function \( \cos^2(kx) \) has a period of \[ \frac{\pi}{k}. \] For \( \cos^2(nx) \), we have \( k = n \), so the period \( P_2 \) is: \[ P_2 = \frac{\pi}{n}. \] ### Step 3: Find the least common multiple (LCM) of the periods The overall period of the function \( f(x) \) will be the least common multiple of \( P_1 \) and \( P_2 \): \[ \text{lcm}(P_1, P_2) = \text{lcm}\left(\frac{\pi}{n}, \frac{\pi}{n}\right) = \frac{\pi}{n}. \] ### Step 4: Set the LCM equal to the given fundamental period We are given that the fundamental period is \( \frac{\pi}{6} \). Therefore, we set: \[ \frac{\pi}{n} = \frac{\pi}{6}. \] ### Step 5: Solve for \( n \) To find \( n \), we can multiply both sides by \( n \) and \( 6 \): \[ 6 = n. \] Thus, we find: \[ n = 6. \] ### Conclusion The value of \( n \) is \( 6 \).

To solve the problem, we need to find the value of \( n \) such that the function \[ f(x) = \frac{\sin(2nx)}{1 + \cos^2(nx)} \] has a fundamental period of \( \frac{\pi}{6} \). ...
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OBJECTIVE RD SHARMA ENGLISH-REAL FUNCTIONS -Chapter Test
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  5. The domain of the function f(x)=sqrt(log((1)/(|sinx|)))

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  8. If f : R -> R is defined by f(x) = [2x] - 2[x] for x in R, where [x] i...

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  9. If N denotes the set of all positive integers and if f : N -> N is def...

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  11. If f(x)={{:(-1, x lt 0),(0, x=0 and g(x)=x(1-x^(2))", then"),(1, x gt ...

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  12. Find the equivalent definition of f(x)=max.{x^(2),(1-x)^(2),2x(1-x)...

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  13. If f(x) is defined on [0,1], then the domain of f(3x^(2)) , is

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  15. The domain of definition of the real function f(x)=sqrt(log(12)x^(2)) ...

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  18. The period of the function sin""((pix)/(2))+cos((pix)/(2)), is

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  20. If x in R , then f(x)=cos^(-1)((1-x^(2))/(1+x^(2))) is equal to

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  21. The equivalent definition of the function f(x)=lim(n to oo)(x^(n)-x^(-...

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