Evaluate
15-4i
Real Part
15
Share
Copied to clipboard
7-\left(-5\right)+5i-\left(-3-i\right)
Subtract -5+5i from 7 by subtracting corresponding real and imaginary parts.
12-5i-\left(-3-i\right)
Subtract -5 from 7.
12-5i+\left(3+i\right)
The opposite of -3-i is 3+i.
12+3+\left(-5+1\right)i
Combine the real and imaginary parts in numbers 12-5i and 3+i.
15-4i
Add 12 to 3. Add -5 to 1.
Re(7-\left(-5\right)+5i-\left(-3-i\right))
Subtract -5+5i from 7 by subtracting corresponding real and imaginary parts.
Re(12-5i-\left(-3-i\right))
Subtract -5 from 7.
Re(12-5i+\left(3+i\right))
The opposite of -3-i is 3+i.
Re(12+3+\left(-5+1\right)i)
Combine the real and imaginary parts in numbers 12-5i and 3+i.
Re(15-4i)
Add 12 to 3. Add -5 to 1.
15
The real part of 15-4i is 15.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}