Evaluate
2+7i
Real Part
2
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\frac{\left(70-20i\right)i}{-10i^{2}}
Multiply both numerator and denominator by imaginary unit i.
\frac{\left(70-20i\right)i}{10}
By definition, i^{2} is -1. Calculate the denominator.
\frac{70i-20i^{2}}{10}
Multiply 70-20i times i.
\frac{70i-20\left(-1\right)}{10}
By definition, i^{2} is -1.
\frac{20+70i}{10}
Do the multiplications in 70i-20\left(-1\right). Reorder the terms.
2+7i
Divide 20+70i by 10 to get 2+7i.
Re(\frac{\left(70-20i\right)i}{-10i^{2}})
Multiply both numerator and denominator of \frac{70-20i}{-10i} by imaginary unit i.
Re(\frac{\left(70-20i\right)i}{10})
By definition, i^{2} is -1. Calculate the denominator.
Re(\frac{70i-20i^{2}}{10})
Multiply 70-20i times i.
Re(\frac{70i-20\left(-1\right)}{10})
By definition, i^{2} is -1.
Re(\frac{20+70i}{10})
Do the multiplications in 70i-20\left(-1\right). Reorder the terms.
Re(2+7i)
Divide 20+70i by 10 to get 2+7i.
2
The real part of 2+7i is 2.
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Integration
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Limits
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