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I dont understand this. could someone give me step by step what the answer would be If?

Questions: If one solution of a quadratic equation is 7-13i, what would the second solution be?

Question 2: solve these, step by step using indicated operations with work!

1. (4-3i) (-7+21)
2. (-7+6i)+(2-3i)+(4+5i)
3. (-6-i)/4-2i
4. (-2-7i)(-2+7i)
5. (5-3i)-(-2-6i)
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User Philip Holly
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1 Answer

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17 votes

Answer:

Below

Explanation:

Question 1:

The quadratic equation is of the form ax^2 + bx + c = 0, where a, b, and c are constants. If one solution of the equation is 7-13i, the other solution must be the complex conjugate of 7-13i, which is 7+13i. To find the complex conjugate of a complex number, you simply need to change the sign of the imaginary part of the number. In this case, the complex conjugate of 7-13i is 7+13i.

Question 2:

1. (4-3i) (-7+21)

To add two complex numbers, we need to add their real parts and imaginary parts separately. In this case, we have:

(4-3i) (-7+21)

= (4 - 7) + (-3i + 21)

= -3 + 18i

2. (-7+6i)+(2-3i)+(4+5i)

To add multiple complex numbers, we can add them one at a time using the same procedure as before. In this case, we have:

(-7+6i)+(2-3i)+(4+5i)

= (-7+2) + (6i - 3i) + (4 + 5i)

= -5 + 3i + 4 + 5i

= -1 + 8i

3. (-6-i)/4-2i

To divide two complex numbers, we need to multiply the numerator and denominator by the complex conjugate of the denominator. In this case, we have:

4. (-6-i)/4-2i

= (-6-i)(4+2i)/(4-2i)(4+2i)

= (-24 - 2i + 6i - i^2)/20

= (-24 + 4 -1)/20

= (-21)/20

= -1.05 - 0.05i

5. (-2-7i)(-2+7i)

To multiply two complex numbers, we use the FOIL method, which involves multiplying the First, Outer, Inner, and Last terms separately and then adding the results. In this case, we have:

(-2-7i)(-2+7i)

= (-2 * -2) + (-2 * 7i) + (-7i * -2) + (-7i * 7i)

= 4 + (-14i) + 14i + 49

= 4 + 49

= 53

6. (5-3i)-(-2-6i)

To subtract two complex numbers, we need to add the first number to the opposite of the second number. In this case, we have:

(5-3i)-(-2-6i)

= (5-3i) + (2 + 6i)

= 7 + 3i

This is the final answer for each of the problems.

User Heff
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