Evaluate
-9-7i
Real Part
-9
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\frac{\left(7-9i\right)i}{1i^{2}}
Multiply both numerator and denominator by imaginary unit i.
\frac{\left(7-9i\right)i}{-1}
By definition, i^{2} is -1. Calculate the denominator.
\frac{7i-9i^{2}}{-1}
Multiply 7-9i times i.
\frac{7i-9\left(-1\right)}{-1}
By definition, i^{2} is -1.
\frac{9+7i}{-1}
Do the multiplications in 7i-9\left(-1\right). Reorder the terms.
-9-7i
Divide 9+7i by -1 to get -9-7i.
Re(\frac{\left(7-9i\right)i}{1i^{2}})
Multiply both numerator and denominator of \frac{7-9i}{i} by imaginary unit i.
Re(\frac{\left(7-9i\right)i}{-1})
By definition, i^{2} is -1. Calculate the denominator.
Re(\frac{7i-9i^{2}}{-1})
Multiply 7-9i times i.
Re(\frac{7i-9\left(-1\right)}{-1})
By definition, i^{2} is -1.
Re(\frac{9+7i}{-1})
Do the multiplications in 7i-9\left(-1\right). Reorder the terms.
Re(-9-7i)
Divide 9+7i by -1 to get -9-7i.
-9
The real part of -9-7i is -9.
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Simultaneous equation
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Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
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