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Conjugates

Solve the first problem 17 problems

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  1. Conjugate product of complex numbers ●○○○○ 10 ptsThe complex numbers aa and bb satisfy ab‾=−1+5ia \overline{b} = -1 + 5i. Find the real part and the imaginary part of a‾ b\overline{a}\, b.
  2. Product of a complex number and its conjugate ●○○○○ 10 ptsGiven a complex number zz satisfying z(1+i)=2iz(1+i)=2i, find z⋅z‾z\cdot\overline{z}.
  3. Product of a complex root and its conjugate ●○○○○ 10 ptsLet zz be a complex number that satisfies z2+3=0z^2 + 3 = 0. Find the value of z⋅z‾z \cdot \overline{z}, where z‾\overline{z} denotes the complex conjugate of zz.
  4. Minimise |z|² under a conjugate constraint ●●○○○ 20 ptsOver complex numbers zz, minimize z∗zz^*z subject to z=z∗+iz = z^* + i, where z∗z^* is the complex conjugate of zz. Write the minimizing zz as z=a+biz = a + bi with real aa and bb, and find aa and bb.
  5. Complex solutions of a conjugate equation ●●○○○ 20 ptsFind all complex numbers zz satisfying zzˉ+z2=zˉ‾−z+2z\bar z+z^2=\overline{\bar z}-z+2. List the solutions in increasing order.
  6. Complex equation with a conjugate ●●○○○ 20 ptsLet zz be a complex number and let z′z' denote its complex conjugate. Find zz if z2+3=z′3−2\frac{z}{2}+3=\frac{z'}{3}-2.

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