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If zr=cos(pi/(3^r))+isin(pi/(3^r)),r=1,2...

If `z_r=cos(pi/(3^r))+isin(pi/(3^r)),r=1,2,3, ,` prove that `z_1z_2z_3 z_oo=idot`

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To prove that \( z_1 z_2 z_3 \ldots = i \), where \( z_r = \cos\left(\frac{\pi}{3^r}\right) + i \sin\left(\frac{\pi}{3^r}\right) \) for \( r = 1, 2, 3, \ldots \), we can follow these steps: ### Step 1: Express \( z_r \) in exponential form Using Euler's formula, we can express \( z_r \) as: \[ z_r = e^{i \frac{\pi}{3^r}} \] ...
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RD SHARMA-COMPLEX NUMBERS-Solved Examples And Exercises
  1. Solve the equation z^2 +|z|=0 , where z is a complex number.

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  2. If z1, z2a n dz3, z4 are two pairs of conjugate complex numbers, prove...

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  3. If zr=cos(pi/(3^r))+isin(pi/(3^r)),r=1,2,3, , prove that z1z2z3 zoo=i...

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  4. If xn=cospi/(2^n)+isinpi/(2^n) , prove that x1x2x3 xoo=-1.

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  5. Find the square roots of the following: 7-24 i (ii) 5+12 i

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  6. Find the square roots of -15-8idot

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  7. Find the number of solutions of z^2+|z|^2=0.

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  8. If ((a^2+1)/(2a-i))^2=x+i y , find the value of x^2+y^2dot

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  9. Let z1a n dz2 be two complex numbers such that ( z )1+i( z )2=0a n d...

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  10. If |z-5i|=|z+5i , then the locus of zdot

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  11. If z1a n dz2 both satisfy z+\bar z =2|z-1| and a r g(z1-z2)=pi/4 , the...

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  12. Show that the complex number z , satisfying are (z-1)/(z+1)=pi/4 lies ...

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  13. If z=(1+7i)/((2-i)^2) , then (a)|z|=2 (b) |z|=1/2 c) a m p(z)=pi/4 (d)...

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  14. The value of (i^5+i^6+i^7+i^8+i^9)/(1+i) is (a) 1/2(1+i) (b) 1/2(1-...

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  15. Write the least positive integral value of n for which ((1+i)/(1-i))^n...

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  16. If f(z)=(7-z)/(1-z^2) , where z=1+2i , then |f(z)| is (a)(|z|)/2 ...

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  17. If z1,z2, z3 are complex numbers such that |z1|=|z2|=|z3|=|1/z1+1/z2+1...

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  18. What is the locus of z , if amplitude of (z-2-3i) is pi/4?

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  19. Write the sum of the series i+i^2+i^3+....... upto 1000 terms.

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  20. The sum and product of two complex numbers are real if and only if the...

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