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x+iy=(1-isqrt3)^100 , then (x,y)=...

`x+iy=(1-isqrt3)^100` , then `(x,y)=`

A

`(2^(99),2^(99)sqrt(3))`

B

`(2^(99),-2^(99)sqrt(3))`

C

`(-2^(99),2^(99)sqrt(3))`

D

none of these

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The correct Answer is:
To solve the problem \( x + iy = (1 - i\sqrt{3})^{100} \), we will follow these steps: ### Step 1: Convert the complex number to polar form First, we need to express \( 1 - i\sqrt{3} \) in polar form. The modulus \( r \) and argument \( \theta \) can be calculated as follows: \[ r = |1 - i\sqrt{3}| = \sqrt{1^2 + (-\sqrt{3})^2} = \sqrt{1 + 3} = \sqrt{4} = 2 \] The argument \( \theta \) is given by: \[ \theta = \tan^{-1}\left(\frac{-\sqrt{3}}{1}\right) = \tan^{-1}(-\sqrt{3}) = -\frac{\pi}{3} \] Thus, we can write: \[ 1 - i\sqrt{3} = 2 \left(\cos\left(-\frac{\pi}{3}\right) + i\sin\left(-\frac{\pi}{3}\right)\right) \] ### Step 2: Apply De Moivre's Theorem Now we can raise this to the power of 100 using De Moivre's Theorem: \[ (1 - i\sqrt{3})^{100} = \left(2 \left(\cos\left(-\frac{\pi}{3}\right) + i\sin\left(-\frac{\pi}{3}\right)\right)\right)^{100} \] This becomes: \[ = 2^{100} \left(\cos\left(-\frac{100\pi}{3}\right) + i\sin\left(-\frac{100\pi}{3}\right)\right) \] ### Step 3: Simplify the angle Next, we need to simplify the angle \( -\frac{100\pi}{3} \): \[ -\frac{100\pi}{3} = -33\pi + \frac{\pi}{3} = -33\pi + \frac{\pi}{3} \quad (\text{since } -33\pi \text{ is a multiple of } 2\pi) \] Thus, we can reduce it to: \[ -\frac{100\pi}{3} \equiv \frac{\pi}{3} \quad (\text{mod } 2\pi) \] ### Step 4: Calculate cosine and sine Now we can find the cosine and sine values: \[ \cos\left(\frac{\pi}{3}\right) = \frac{1}{2}, \quad \sin\left(\frac{\pi}{3}\right) = \frac{\sqrt{3}}{2} \] ### Step 5: Substitute back Substituting these values back, we have: \[ (1 - i\sqrt{3})^{100} = 2^{100} \left(\frac{1}{2} + i\frac{\sqrt{3}}{2}\right) \] This simplifies to: \[ = 2^{100} \cdot \frac{1}{2} + i \cdot 2^{100} \cdot \frac{\sqrt{3}}{2} = 2^{99} + i \cdot 2^{99}\sqrt{3} \] ### Step 6: Identify \( x \) and \( y \) From the expression \( x + iy = 2^{99} + i \cdot 2^{99}\sqrt{3} \), we can identify: \[ x = 2^{99}, \quad y = 2^{99}\sqrt{3} \] ### Final Result Thus, the final answer is: \[ (x, y) = (2^{99}, 2^{99}\sqrt{3}) \]

To solve the problem \( x + iy = (1 - i\sqrt{3})^{100} \), we will follow these steps: ### Step 1: Convert the complex number to polar form First, we need to express \( 1 - i\sqrt{3} \) in polar form. The modulus \( r \) and argument \( \theta \) can be calculated as follows: \[ r = |1 - i\sqrt{3}| = \sqrt{1^2 + (-\sqrt{3})^2} = \sqrt{1 + 3} = \sqrt{4} = 2 \] ...
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OBJECTIVE RD SHARMA ENGLISH-COMPLEX NUMBERS -Chapter Test
  1. x+iy=(1-isqrt3)^100 , then (x,y)=

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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. Prove that for positive integers n(1) and n(2), the value of express...

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  4. The value of abs(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+ i sqrt(3))/(1-isqrt(3)))+ ((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=0andA+B+C=180^(@) then the value of...

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  9. Find the sum 1xx(2-omega)xx(2-omega^(2))+2xx(-3-omega)xx(3-omega^(2))+...

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

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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))^(n2) is real iff

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  13. If |{:(6i,3i,1),(4,3i,-1),(20,3,i):}|=x+iy, then (x, y) is equal to

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  14. If cosalpha+2cosbeta+3cosgamma=sinalpha+2sinbeta+3singamma=0,t h e nt ...

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  15. If cosalpha+2cosbeta+3cosgamma=sinalpha+2sinbeta+3singamma=0,t h e nt ...

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

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

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

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

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  20. The vertices of a square are z(1),z(2),z(3) and z(4) taken in the anti...

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  21. Let lambda in R . If the origin and the non-real roots of 2z^2+2z+lam...

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