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Simplify and express each of the followi...

Simplify and express each of the following in the form (a + ib) :
`(i)" "((5)/(-3+2i)+(2)/(1-i))((4-5i)/(3+2i))" "(ii)" "((1)/(1-4i)-(2)/(1+i))((1-i)/(5+3i))`

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To simplify the given expressions and express them in the form \( a + ib \), we will follow a systematic approach for each part of the question. ### Part (i): Simplify and express \( \left( \frac{5}{-3 + 2i} + \frac{2}{1 - i} \right) \left( \frac{4 - 5i}{3 + 2i} \right) \). **Step 1: Simplify \( \frac{5}{-3 + 2i} \)** To simplify \( \frac{5}{-3 + 2i} \), we multiply the numerator and denominator by the conjugate of the denominator, which is \( -3 - 2i \): \[ \frac{5(-3 - 2i)}{(-3 + 2i)(-3 - 2i)} = \frac{-15 - 10i}{(-3)^2 + (2)^2} = \frac{-15 - 10i}{9 + 4} = \frac{-15 - 10i}{13} \] So, \[ \frac{5}{-3 + 2i} = -\frac{15}{13} - \frac{10}{13}i \] **Step 2: Simplify \( \frac{2}{1 - i} \)** Similarly, we multiply the numerator and denominator by the conjugate of the denominator, which is \( 1 + i \): \[ \frac{2(1 + i)}{(1 - i)(1 + i)} = \frac{2 + 2i}{1^2 + 1^2} = \frac{2 + 2i}{2} = 1 + i \] **Step 3: Combine the two fractions** Now we add the two results: \[ -\frac{15}{13} - \frac{10}{13}i + 1 + i = \left(1 - \frac{15}{13}\right) + \left(1 - \frac{10}{13}\right)i \] Calculating the real and imaginary parts: \[ 1 - \frac{15}{13} = \frac{13}{13} - \frac{15}{13} = -\frac{2}{13} \] \[ 1 - \frac{10}{13} = \frac{13}{13} - \frac{10}{13} = \frac{3}{13} \] So, \[ \frac{5}{-3 + 2i} + \frac{2}{1 - i} = -\frac{2}{13} + \frac{3}{13}i \] **Step 4: Multiply by \( \frac{4 - 5i}{3 + 2i} \)** Now we simplify \( \frac{4 - 5i}{3 + 2i} \) by multiplying by the conjugate of the denominator: \[ \frac{(4 - 5i)(3 - 2i)}{(3 + 2i)(3 - 2i)} = \frac{12 - 8i - 15i + 10}{9 + 4} = \frac{22 - 23i}{13} \] **Step 5: Multiply the results** Now we multiply: \[ \left(-\frac{2}{13} + \frac{3}{13}i\right) \cdot \frac{22 - 23i}{13} \] Calculating this gives: \[ \frac{(-2)(22) + (-2)(-23i) + (3i)(22) + (3i)(-23i)}{169} \] \[ = \frac{-44 + 46i + 66i + 69}{169} = \frac{25 + 112i}{169} \] Thus, the final result for part (i) is: \[ \frac{25}{169} + \frac{112}{169}i \] ### Part (ii): Simplify and express \( \left( \frac{1}{1 - 4i} - \frac{2}{1 + i} \right) \left( \frac{1 - i}{5 + 3i} \right) \). **Step 1: Simplify \( \frac{1}{1 - 4i} \)** Multiply by the conjugate: \[ \frac{1(1 + 4i)}{(1 - 4i)(1 + 4i)} = \frac{1 + 4i}{1 + 16} = \frac{1 + 4i}{17} \] **Step 2: Simplify \( \frac{2}{1 + i} \)** Multiply by the conjugate: \[ \frac{2(1 - i)}{(1 + i)(1 - i)} = \frac{2 - 2i}{1 + 1} = \frac{2 - 2i}{2} = 1 - i \] **Step 3: Combine the two fractions** Now we subtract: \[ \frac{1 + 4i}{17} - (1 - i) = \frac{1 + 4i - 17 + 17i}{17} = \frac{-16 + 21i}{17} \] **Step 4: Multiply by \( \frac{1 - i}{5 + 3i} \)** First, simplify \( \frac{1 - i}{5 + 3i} \): \[ \frac{(1 - i)(5 - 3i)}{(5 + 3i)(5 - 3i)} = \frac{5 - 3i - 5i - 3(-1)}{25 + 9} = \frac{8 - 8i}{34} = \frac{4 - 4i}{17} \] **Step 5: Multiply the results** Now multiply: \[ \left(\frac{-16 + 21i}{17}\right) \cdot \left(\frac{4 - 4i}{17}\right) = \frac{(-16)(4) + (-16)(-4i) + (21i)(4) + (21i)(-4i)}{289} \] \[ = \frac{-64 + 64i + 84i - 84}{289} = \frac{-148 + 148i}{289} \] Thus, the final result for part (ii) is: \[ -\frac{148}{289} + \frac{148}{289}i \] ### Final Answers: - Part (i): \( \frac{25}{169} + \frac{112}{169}i \) - Part (ii): \( -\frac{148}{289} + \frac{148}{289}i \)

To simplify the given expressions and express them in the form \( a + ib \), we will follow a systematic approach for each part of the question. ### Part (i): Simplify and express \( \left( \frac{5}{-3 + 2i} + \frac{2}{1 - i} \right) \left( \frac{4 - 5i}{3 + 2i} \right) \). **Step 1: Simplify \( \frac{5}{-3 + 2i} \)** To simplify \( \frac{5}{-3 + 2i} \), we multiply the numerator and denominator by the conjugate of the denominator, which is \( -3 - 2i \): ...
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RS AGGARWAL-COMPLEX NUMBERS AND QUADRATIC EQUATIONS-EXERCISE 5 B
  1. Simplify and express each of the following in the form (a + ib) : {:...

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  2. Express each of the following in the form (a + ib) : {:((i),(1)/((4+...

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  3. Simplify and express each of the following in the form (a + ib) : (i...

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  4. Show that (i)" "{((3+2i))/((2-3i))+((3-2i))/((2+3i))} is purely real...

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  5. Find the real values of theta for which the complex number (1+i costhe...

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  6. If |z + i| = |z - i|, prove that z is real.

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  7. Give an example of two complex numbers z(1) and z(2) such that z(1) ne...

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  8. Find the conjugate of each of the following : {:((i),(-5-2i),(ii),(1...

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  9. Find the modulus of each of the following : {:((i),(3+sqrt(-5)),(ii)...

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  10. Find the multiplicative inverse of each of the following : (i)" "(1-...

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  11. If ((1-i)/(1+i))^(100)=a+i b ,\ fin d\ (a , b)

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  12. If ((1+i)/(1-i))^3-((1-i)/(1+i))^3=x+i y ,\ fin d\ (x , y)

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  13. If x + i y =(a+i b)/(a-i b),prove that x^2+y^2=1.

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  14. If a+i b=(c+i)/(c-i) , where c is real, prove that:a^2+b^2=1a n d b/a=...

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  15. Show that (1-i)^(n)(1-(1)/(i))^(n)=2^(n) for all n in N

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  16. What is the smallest positive integer n for which (1+i)^(2n)=(1-i)^(2n...

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  17. Prove that: x^4=4=(x+1+i)(x+1-i)(x-1+i(x-1-i)dot)

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  18. if a = costheta +i sin theta , prove that (1+a)/(1-a) = cot(theta/2)i

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  19. If z1=2-i ,\ z2=1+i , find |(z1+z2+1)/(z1-z2+i)|

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  20. Find the real values of x and y for which : {:((i),(1-i)x+(1+i)y=1 -...

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