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What are the two solutions to this math problem?

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4 Answers

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  • ?
    Lv 7
    5 months ago

    Sqrt (55 + 48i)

    a^2 + 2 i a b - b^2 = 55 + 48 i

    ab = 24 

    (a + b)(a - b) = 55 

    (8 + 3)(8 - 3) = 55 or (64 - 9)

    (8 + 3i)^2 = 55 + 48i

    (-8 - 3i)^2 = 55 + 48i

     

  • Ian H
    Lv 7
    5 months ago

    (a + bi)^2 = a^2 – b^2 +2abi

    ab = 24 = 6*4 = 8*3

    a^2 – b^2 = 55 = 64 – 9

    The roots were 8 + 3i and -8 - 3i

  • 5 months ago

    We have:

    a + bi = √(55 + 48i)

    If we square both sides and simplify the left side we get:

    (a + bi)² = 55 + 48i

    a² + 2abi + b²i² = 55 + 48i

    i² = -1, so:

    a² + 2abi - b² = 55 + 48i

    Now we can group that into standard complex number form:

    a² - b² + 2abi = 55 + 48i

    (a² - b²) + (2ab)i = 55 + 48i

    We can now compare the real portion of the two sides and make an equation and the complex portion of the two sides to make a second equation:

    a² - b² = 55 and 2ab = 48

    We now have a system of two equations and two unknowns that can be solved.

    2ab = 48

    ab = 24

    b = 24/a

    a² - b² = 55

    a² - (24/a)² = 55

    a² - 576/a² = 55

    a⁴ - 576 = 55a²

    a⁴ - 55a² - 576 = 0

    If we substitute x = a²:

    x² - 55x - 576 = 0

    x = [ -b ± √(b² - 4ac)] / (2a)

    x = [ -(-55) ± √((-55)² - 4(1)(-576))] / (2 * 1)

    x = [ 55 ± √(3025 + 2304)] / 2

    x = [ 55 ± √(5329)] / 2

    x = (55 ± 73) / 2

    x = -18/2 and 128/2

    x = -9 and 64

    If we substitute those back into a²:

    x = -9 and x = 64

    a² = -9 and a² = 64

    a = ±3i and a = ±8

    "a" must be real so we can throw out the first two solutions:

    a = ±8

    Now we can find the two "b" values:

    b = 24/a

    b = 24/(-8) and b = 24/8

    b = -3 and b = 3

    So your two solutions are:

    -8 - 3i and 8 + 3i

  • ?
    Lv 7
    5 months ago

    √(55+48i) = +√(55+48i)  and -√(55+48i)   ............ANS

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