7.Perform the indicated operation and write the answer in standard form. a)  (-2+2¡)-(-3-¡) b) -5-3¡÷3+4¡?

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  • 4 weeks ago

    I suspect that your "¡" means the same thing as our "i" (the "imaginary" number such that i^2 = -1)

    (-2 + 2i) - (-3i)

    distribute the minus sign into the last bracket

    (-2 + 2i) + 3i

    add real with real, and imaginary with imaginary

    -2 + 5i

    This is a Complex numner (a mix of real and imaginary) where the real part is equal to -2 and the imaginary part is equal to +5

    -----

    (-5 - 3i) / (3 + 4i)

    This is a bit trickier.

    You must multiply above and below by the value "1" written as the conjugate of the denominator over itself.

    1 = (3 - 4i) / (3 - 4i)

    Something divided by itself is always equal to 1 (except 0/0 -- but in this case, 3 - 4i is not equal to zero)

    (-5 - 3i) / (3 + 4i) = (-5 - 3i) / (3 + 4i) * "1"

    (-5 - 3i)(3 - 4i) / (3 + 4i)(3 - 4i) =

    (-15 + 20i -9i  + 12i^2) / (9 - 16i^2) =

    Using i^2 = -1

    (-15 - 12 + 11i) / (9 + 16) =

    (-27 + 11i) / 25

    One (of many) standard form is

    (27/25) + (11/25)i

    or

    1.08 + 0.44i

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