find value of b

Let z1 and z2 be complex roots of 3z2+3z+b=0.If the origin,together with the points represented by z1 and z2 forms equilateral triangle,then find b.

2 Answers

1
Prashant Shekhar ·

b=1

1
Prashant Shekhar ·

Use these equations
z1+z2=-1 ... (i)
z1z2=b/3 ... (ii)
and

since z1, z2 and originn form an eq. triangle.
z2=z1e±iπ/3 ....(iii)

(Either sign will give the same result... you can start with whatever sign you like)

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