Math Problem Statement

et z_1 =(-i)/(-1+i),z_2=1+i/(1-i) and z_3=1/10[2(i-1)i+(-i+sqrt3)^3]+(1-i)bar((1-i))]

express /bar(z_1z_2)/z_3,z_1barz_2/z3 and barz_1/barz_3z_2 in both polar and standard forms

Solution

To solve the problem, we need to first express z1z_1, z2z_2, and z3z_3 in their standard forms (rectangular forms) and then compute the required expressions.

Step 1: Simplify z1=i1+iz_1 = \frac{-i}{-1 + i}

Simplify the expression by multiplying the numerator and the denominator by the conjugate of the denominator:

z1=i1+i×1i1i=i(1i)(1+i)(1i)z_1 = \frac{-i}{-1 + i} \times \frac{-1 - i}{-1 - i} = \frac{-i(-1 - i)}{(-1 + i)(-1 - i)}

The denominator is: (1+i)(1i)=1+1=2(-1 + i)(-1 - i) = 1 + 1 = 2

The numerator is: i(1i)=i+1-i(-1 - i) = i + 1

So, z1=1+i2=12+i2z_1 = \frac{1 + i}{2} = \frac{1}{2} + \frac{i}{2}

Step 2: Simplify z2=1+i1iz_2 = \frac{1+i}{1-i}

Similarly, simplify by multiplying by the conjugate of the denominator:

z2=1+i1i×1+i1+i=(1+i)2(1i)(1+i)=1+2i11+1=2i2=iz_2 = \frac{1 + i}{1 - i} \times \frac{1 + i}{1 + i} = \frac{(1 + i)^2}{(1 - i)(1 + i)} = \frac{1 + 2i - 1}{1 + 1} = \frac{2i}{2} = i

Step 3: Simplify z3=110[2(i1)i+(i+3)3]+(1i)(1i)z_3 = \frac{1}{10} \left[ 2(i - 1)i + (-i + \sqrt{3})^3 \right] + (1-i)\overline{(1-i)}

First, simplify each term:

2(i1)i=2i(i1)=2i22i=22i2(i-1)i = 2i(i-1) = 2i^2 - 2i = -2 - 2i

For the cubic term, (i+3)3(-i + \sqrt{3})^3:

Let w=i+3w = -i + \sqrt{3}. Then: w2=(i+3)2=(i)2+2(i)(3)+(3)2=12i3+3=22i3w^2 = (-i + \sqrt{3})^2 = (-i)^2 + 2(-i)(\sqrt{3}) + (\sqrt{3})^2 = -1 - 2i\sqrt{3} + 3 = 2 - 2i\sqrt{3}

w3=w2(i+3)=(22i3)(i+3)w^3 = w^2(-i + \sqrt{3}) = (2 - 2i\sqrt{3})(-i + \sqrt{3})

Expanding:

= -2i + 2\sqrt{3} - 6 + 2i^2 = -2i + 2\sqrt{3} - 6 + 2i(-i) + 6\sqrt{3} = (-6 + 2i + 6) + (2i - 6i) = -2\sqrt{3}i$$ So: $$(-i + \sqrt{3})^3 = -6 + 2\sqrt{3} + i(-2 - 6i)$$ Adding the above with $$-2 - 2i + (-6 + 2\sqrt{3}) + i(\overline{1 - i})$$ we add the following: Conjugate: $$\overline{(1 - i)} = 1 + i$$: $$= (-6 + 2\sqrt{3}) =$$ equals: ### Expression forms: Express in simplified: $$z_3 = -6 + 2\sqrt{3} + (1+i)(1-i)$$ Combining all of these to a real simplified expression on both $$/bar(z_1z_2)/z_3,z_1barz_2/z3$$. Tip: Solve math on both formats by steps.

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Math Problem Analysis

Mathematical Concepts

Complex Numbers
Polar Form
Rectangular Form
Conjugates

Formulas

z = a + bi
|z| = sqrt(a^2 + b^2)
Conjugate of z: bar(z) = a - bi
Multiplication of complex numbers in polar form: r1 * r2 [cos(θ1 + θ2) + i*sin(θ1 + θ2)]

Theorems

De Moivre's Theorem
Complex Number Conjugation
Modulus of Complex Numbers

Suitable Grade Level

Undergraduate