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Convert ((1)/(2)+2i)^(3) in the form of...

Convert ` ((1)/(2)+2i)^(3)` in the form of `a+ib`.

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To convert \( \left( \frac{1}{2} + 2i \right)^3 \) into the form \( a + ib \), we can use the binomial theorem. Here’s how to do it step by step: ### Step 1: Identify the components We have \( z = \frac{1}{2} + 2i \). We need to compute \( z^3 \). ### Step 2: Apply the binomial theorem Using the binomial theorem, we can expand \( (a + b)^3 \): \[ (a + b)^3 = a^3 + 3a^2b + 3ab^2 + b^3 \] In our case, let \( a = \frac{1}{2} \) and \( b = 2i \). ### Step 3: Calculate each term 1. Calculate \( a^3 \): \[ a^3 = \left( \frac{1}{2} \right)^3 = \frac{1}{8} \] 2. Calculate \( 3a^2b \): \[ 3a^2b = 3 \left( \frac{1}{2} \right)^2 (2i) = 3 \cdot \frac{1}{4} \cdot 2i = \frac{3}{2}i \] 3. Calculate \( 3ab^2 \): \[ 3ab^2 = 3 \left( \frac{1}{2} \right) (2i)^2 = 3 \cdot \frac{1}{2} \cdot 4(-1) = -6 \] 4. Calculate \( b^3 \): \[ b^3 = (2i)^3 = 8i^3 = 8(-i) = -8i \] ### Step 4: Combine all terms Now, combine all the calculated terms: \[ z^3 = a^3 + 3a^2b + 3ab^2 + b^3 = \frac{1}{8} + \frac{3}{2}i - 6 - 8i \] ### Step 5: Simplify the expression Combine the real parts and the imaginary parts: 1. Real part: \[ \frac{1}{8} - 6 = \frac{1}{8} - \frac{48}{8} = -\frac{47}{8} \] 2. Imaginary part: \[ \frac{3}{2}i - 8i = \frac{3}{2}i - \frac{16}{2}i = -\frac{13}{2}i \] ### Final Result Thus, we can write: \[ \left( \frac{1}{2} + 2i \right)^3 = -\frac{47}{8} - \frac{13}{2}i \] This is in the form \( a + ib \) where \( a = -\frac{47}{8} \) and \( b = -\frac{13}{2} \).

To convert \( \left( \frac{1}{2} + 2i \right)^3 \) into the form \( a + ib \), we can use the binomial theorem. Here’s how to do it step by step: ### Step 1: Identify the components We have \( z = \frac{1}{2} + 2i \). We need to compute \( z^3 \). ### Step 2: Apply the binomial theorem Using the binomial theorem, we can expand \( (a + b)^3 \): \[ ...
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NAGEEN PRAKASHAN ENGLISH-COMPLEX NUMBERS AND QUADRATIC EQUATION -MISCELLANEOUS EXERCISE
  1. Convert ((1)/(2)+2i)^(3) in the form of a+ib.

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  2. Evaluate : [i^(18)+(1/i)^(25)]^3

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  3. For any two complex numbers z1and z2, prove that R e(z1z2)=R ez1R e z2...

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  4. Reduce (1/(1-4i)-2/(1+i))((3-4i)/(5+i))to the standard form.

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  5. If under root of (a+i b)/(c+i d)=x+i y , Prove (a^2+b^2)/(c^2+d^2)=(x...

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  6. Convert the following in the polar form : (i) (1+7i)/((2-i)^2) (ii) (...

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  7. Solve the equation : 3x^2-4x+(20)/3=0

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  8. Solve the equation :x^2-2x+3/2=0

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  9. Solve the equation :27 x^2-10 x+1=0

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  10. Solve the following quadratic: 21 x^2-28 x+10=0

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

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

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  13. If z1=2-i ,\ +2=-2+i , find : R e((z1z2)/(z1))

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  14. Find the modulus and argument of the complex number (1+2i)/(1-3i).

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  15. Find the real numbers x and y if (x-i y)(3+5i)is the conjugate of -6-...

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  16. Find the modulus of (1+i)/(1-i)-(1-i)/(1+i)

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  17. If (x+i y)^3=u+i v ,then show that u/x+v/y=4(x^2-y^2).

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  18. If alphaand betaare different complex numbers with |beta|=1,then fin...

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  19. Find the number of non-zero integral solution of the equation |1-i|^x=...

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  20. If (a + ib) (c + id) (e + if) (g + ih) = A + iB, then show that (a^2 +...

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  21. If ((1+i)/(1-i))^m=1, then find the least positive integral value of m...

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