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If (1+2i)/(2+i)=r(costheta+isintheta) th...

If `(1+2i)/(2+i)=r(costheta+isintheta)` then

A

r=1,`theta=tan^(-1)(3/4)`

B

`r=sqrt5`,theta=tan^(-1)4/3`

C

r=1,`theta=tan^(-1)4/3`

D

none of these

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The correct Answer is:
A
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PATHFINDER-COMPLEX NUMBER-QUESTION BANK
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  3. If (1+2i)/(2+i)=r(costheta+isintheta) then

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  7. Let z1,z2,z3 be three points on absz=1 let theta1,theta2 and theta3 be...

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  8. If z1,z2 are two non zero complex numbers such that z1/z2+z2/z1=1 then...

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  9. The complex numbers z1,z2 and z3 satisfying (z1-z3)/(z2-z3)=(1-isqrt3)...

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  12. Let z1 nez2 are two points in the Argand plane if a abs(z1)=b abs(z2) ...

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  13. The least positive integer n for which ((1+i)/(1-i))^n=2/pisin^(-1)((1...

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  14. If x=2+5i then the value of the expression x^3-5x^2+33x-49 is

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  15. The square root of (1+i) is

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  16. The curve represented by Im(z^2)=c^2 is

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  17. If z be a complex number satisfying z^4+z^3+2z^2+z+1=0 then absz is eq...

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  18. If omega is complex cube root of unity then (3+5omega+3omega^2)^2+(3+3...

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  19. Let 0lealphalepi/2 be a fixed angle.if p=(costheta,sintheta) and Q=(co...

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