# The real part of complex number $z= 2a+i\left ( 7-a \right )$ when z becomes purely real will be  $\left ( a\: \epsilon\: R \right )$ Option 1) $14$ Option 2) $-14$ Option 3) $16$ Option 4) $-16$

V Vakul

z will be purely real if 7-a=0

i.e. a=7

So, real part of z becomes 2x7=14

$\therefore$ Option A

Purely Real Complex Number -

$z=x+iy, x\epsilon R, \boldsymbol{y=0}$

& i2=-1

- wherein

Real part of z = Re (z) = x & Imaginary part of z = Im (z) = y

Option 1)

$14$

This is correct

Option 2)

$-14$

This is incorrect

Option 3)

$16$

This is incorrect

Option 4)

$-16$

This is incorrect

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