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Solve the equation x^(2)+ 2ix+15=0....

Solve the equation `x^(2)+ 2ix+15=0`.

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To solve the equation \( x^2 + 2ix + 15 = 0 \), we can use the quadratic formula or factorization. Let's proceed step by step using the quadratic formula. ### Step 1: Identify the coefficients The given equation is in the standard form of a quadratic equation \( ax^2 + bx + c = 0 \). Here, - \( a = 1 \) - \( b = 2i \) - \( c = 15 \) ### Step 2: Apply the quadratic formula The quadratic formula is given by: \[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] ### Step 3: Calculate the discriminant First, we need to calculate the discriminant \( b^2 - 4ac \): \[ b^2 = (2i)^2 = 4i^2 = 4(-1) = -4 \] \[ 4ac = 4 \cdot 1 \cdot 15 = 60 \] Now, substituting these values into the discriminant: \[ b^2 - 4ac = -4 - 60 = -64 \] ### Step 4: Substitute into the quadratic formula Now substitute \( b \), \( a \), and the discriminant into the quadratic formula: \[ x = \frac{-2i \pm \sqrt{-64}}{2 \cdot 1} \] ### Step 5: Simplify the square root We know that \( \sqrt{-64} = \sqrt{64} \cdot \sqrt{-1} = 8i \). Thus, we have: \[ x = \frac{-2i \pm 8i}{2} \] ### Step 6: Split into two cases We can split this into two cases: 1. \( x = \frac{-2i + 8i}{2} = \frac{6i}{2} = 3i \) 2. \( x = \frac{-2i - 8i}{2} = \frac{-10i}{2} = -5i \) ### Step 7: Write the final solutions The solutions to the equation \( x^2 + 2ix + 15 = 0 \) are: \[ x = 3i \quad \text{and} \quad x = -5i \]

To solve the equation \( x^2 + 2ix + 15 = 0 \), we can use the quadratic formula or factorization. Let's proceed step by step using the quadratic formula. ### Step 1: Identify the coefficients The given equation is in the standard form of a quadratic equation \( ax^2 + bx + c = 0 \). Here, - \( a = 1 \) - \( b = 2i \) - \( c = 15 \) ...
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NAGEEN PRAKASHAN ENGLISH-COMPLEX NUMBERS AND QUADRATIC EQUATION -MISCELLANEOUS EXERCISE
  1. Solve the equation x^(2)+ 2ix+15=0.

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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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