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Express the following complex number in exponential form:

(3−4i)
a. 5e⁻⁵.³⁶ᶦ
b. −5​√e⁻⁵.³⁶ᶦ
c. 5e⁵.³⁶ᶦ
d. √5​e⁵.³⁶ᶦ

1 Answer

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Final answer:

The complex number (3−4i) can be expressed in exponential form by finding its magnitude, which is 5, and its argument which is approximately −0.93 radians. thus the exponential form is approximately 5e^{-i*0.93}.

Step-by-step explanation:

To express the complex number (3−4i) in exponential form, we first need to find the magnitude (r) and the argument (θ) of the complex number. the magnitude can be found using the formula √(a² + b²), where 'a' is the real part and 'b' is the imaginary part of the complex number. the argument is the angle the vector representing the complex number makes with the positive real axis, in this case we can find it using the arctan(b/a) formula.

The magnitude r is:

  • r = √(3² + (−4)²) = √(9 + 16) = √25 = 5

The argument θ is:

  • θ = arctan(-4/3)

To find θ in radians, we know that tan(θ) = -4/3 and that θ is in the fourth quadrant (since cosine is positive and sine is negative in the fourth quadrant), hence θ = -arctan(4/3) ≈ -0.93 radians (which is equivalent to -53.13 degrees).

Finally, express (3−4i) in exponential form:

  • z = re^{iθ} = 5e^{-i*0.93}

Looking at the options provided, the correct answer in exponential form resembles the result we obtained, option a. 5e⁻⁵.⁳⁶ᵗ appears to match closely after considering minor typographical differences. however please carefully check against your original options as proper formatting of the answer choices might have been lost.

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