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(sinpi//8+icospi//8)^(8)/(sinpi//8-icosp...

`(sinpi//8+icospi//8)^(8)/(sinpi//8-icospi//8)^(8)=`

A

`-1`

B

0

C

1

D

2i

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The correct Answer is:
To solve the expression \((\sin \frac{\pi}{8} + i \cos \frac{\pi}{8})^8 / (\sin \frac{\pi}{8} - i \cos \frac{\pi}{8})^8\), we can use the properties of complex numbers and Euler's formula. Here’s a step-by-step breakdown of the solution: ### Step 1: Rewrite the expression using Euler's Formula We know that \(e^{i\theta} = \cos \theta + i \sin \theta\). We can manipulate our expression to fit this form. Let: \[ z_1 = \sin \frac{\pi}{8} + i \cos \frac{\pi}{8} \] \[ z_2 = \sin \frac{\pi}{8} - i \cos \frac{\pi}{8} \] ### Step 2: Express \(z_1\) and \(z_2\) in exponential form Using the identity \(i \cos \theta = e^{i\frac{\pi}{2}} \sin \theta\), we can express \(z_1\) and \(z_2\) as: \[ z_1 = \sin \frac{\pi}{8} + i \cos \frac{\pi}{8} = e^{i(\frac{\pi}{2} - \frac{\pi}{8})} = e^{i\frac{3\pi}{8}} \] \[ z_2 = \sin \frac{\pi}{8} - i \cos \frac{\pi}{8} = e^{-i(\frac{\pi}{2} - \frac{\pi}{8})} = e^{-i\frac{3\pi}{8}} \] ### Step 3: Raise both to the power of 8 Now we raise both \(z_1\) and \(z_2\) to the power of 8: \[ z_1^8 = \left(e^{i\frac{3\pi}{8}}\right)^8 = e^{i3\pi} = -1 \] \[ z_2^8 = \left(e^{-i\frac{3\pi}{8}}\right)^8 = e^{-i3\pi} = -1 \] ### Step 4: Form the final expression Now we substitute back into our original expression: \[ \frac{z_1^8}{z_2^8} = \frac{-1}{-1} = 1 \] ### Conclusion Thus, the final result of the expression \((\sin \frac{\pi}{8} + i \cos \frac{\pi}{8})^8 / (\sin \frac{\pi}{8} - i \cos \frac{\pi}{8})^8\) is: \[ \boxed{1} \]

To solve the expression \((\sin \frac{\pi}{8} + i \cos \frac{\pi}{8})^8 / (\sin \frac{\pi}{8} - i \cos \frac{\pi}{8})^8\), we can use the properties of complex numbers and Euler's formula. Here’s a step-by-step breakdown of the solution: ### Step 1: Rewrite the expression using Euler's Formula We know that \(e^{i\theta} = \cos \theta + i \sin \theta\). We can manipulate our expression to fit this form. Let: \[ z_1 = \sin \frac{\pi}{8} + i \cos \frac{\pi}{8} ...
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Express the following in a + ib form: (i) ((cos theta+ isin theta)/(sin theta + icos theta))^(4) (ii) ((cos 2theta -isin2theta)^(4)(cos4theta +isin4theta)^(-5))/((cos 3theta +isin3theta)^(-2) (cos 3theta -isin 3theta)^(-9)) (iii) ((sinpi//8 +icos pi//8)^(8))/((sinpi//8-icospi//8)^(8))

{(1+cospi//8+isinipi//8)/(1+cospi//8-isinpi//8)}^(8)=

((sin((pi)/(8))+i cos((pi)/(8)))^(8))/((sin((pi)/(8))-i cos((pi)/(8)))^(8)) =

The expression [(1+sin((pi)/(8))+i cos((pi)/(8)))/(1+sin((pi)/(8))-i cos((pi)/(8)))]^(8)

Find the Values of sin (pi/8) ,cos (pi/ 8) ,sec (pi/8) ,cosec (pi/8) ,tan (pi/8) and Cot (pi/8)

Prove that cos^(2)(pi/8-A/2)-cos^(2)(pi/8+A/2) [1-sin^(2)(pi/8-A/2)]-[1-sin^(2)(pi/8+A/2)] =sin^(2)(pi/8+A/2)-sin^(2)(pi/8-A/2) =sin{(pi/8+A/2)+(pi/8-A/2)} sin{(pi/8+A/2)-(pi/8-A/2)} s=sinpi/4. sinA=1/sqrt(2)sinA =RHS Hence Proved.

[(1 + cos ((pi) / (8)) + i sin ((pi) / (8))) / (1 + cos ((pi) / (8)) - sin ((pi) / (8 )))] ^ (8) =?

OBJECTIVE RD SHARMA-COMPLEX NUMBERS -Chapter Test
  1. (sinpi//8+icospi//8)^(8)/(sinpi//8-icospi//8)^(8)=

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  2. The locus of the center of a circle which touches the circles |z-z1|=a...

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  3. If n1, n2 are positive integers, then (1 + i)^(n1) + ( 1 + i^3)^(n1) +...

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  4. The modulus of sqrt(2i)-sqrt(-2i) is

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  5. Prove that the triangle formed by the points 1,(1+i)/(sqrt(2)),a n di ...

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  6. The value of (1+isqrt(3))/(1-isqrt(3))^(6)+(1-isqrt(3))/(1+isqrt(3))^(...

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  7. If alpha+ibeta=tan^(-1) (z), z=x+iy and alpha is constant, the locus o...

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  8. If cosA+cosB+cosC=0,sinA + sinB + sinC=0and A+B+C=180^0, then the valu...

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  9. The value of the expression 1.(2-omega).(2-omega^2)+2.(3-omega)(3-omeg...

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  10. The value of the expression (1+1/omega)(1+1/omega^(2))+(2+1/omega)(2+...

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  11. The condition that x^(n+1)-x^(n)+1 shall be divisible by x^(2)-x+1 is ...

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  12. The expression (1+i)^(n1)+(1+i^(3))^(n(2)) is real iff

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  13. |{:("6i " "-3i " "1" ),("4 " " 3i" " -1"),("20 " "3 " " i"):}|=x+iy th...

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  14. The centre of a square ABCD is at z0dot If A is z1 , then the centroid...

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  15. If cosalpha+2cosbeta+3cosgamma=sinalpha+2sinbeta+3singamma=0 and alpha...

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  16. If cosalpha+2cosbeta+3cosgamma=sinalpha+2sinbeta+3singamma=0 and alpha...

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  17. Sum of the series sum(r=0)^n (-1)^r ^nCr[i^(5r)+i^(6r)+i^(7r)+i^(8r)] ...

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  18. If az(1)+bz(2)+cz(3)=0 for complex numbers z(1),z(2),z(3) and real num...

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  19. If 2z1-3z2 + z3=0, then z1, z2 and z3 are represented by

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  20. Re((z+4)/(2z-1)) = 1/2, then z is represented by a point lying on

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  21. The vertices of a square are z1,z2,z3 and z4 taken in the anticlockwis...

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