Any complex expression 
Accuracy calculation (signs after a comma) 

You entered the following expression 
Final result of expression 
Updating: For September 12, 2017, data input is simplified. Now it is possible to enter expression without multiplication sign. For example 3 (2+i) (4+sin (i)). If the wrong calculation, a request in the bottom of the page noticed to designate a mistake in the form of the comment. Thanks!
Allows to calculate result of any complex expression with any quantity of brackets, any length and with any numbers (both valid, and imaginary)
Arithmetic expression means itself expression which uses 4 main operations: multiplication, division, addition and subtraction.
Let's remind as these operations are made: Addition of two complex numbers
Subtraction of two complex numbers
Multiplication of two complex numbers
Division of two complex numbers
This boat still can use the fifth operation  exponentiation, and also all main trigonometrical functions (a sine, a cosine, a tangent), the inverse trigonometrical functions, capture of a logarithm and exhibitors.
Notice, these functions can use both the valid arguments, and complex that opens ample opportunities on calculation of expressions.
Exponentiation is carried out on the known formula of Moivre.
Number degree, can be both valid and imaginary.
The calculator works, is serviceable, and does not make a mistake at correct input of expression.
As it was already told, expression on complexity can be unlimited by the sizes and have a set of brackets.
Line any expression without any functions can be. The following operations can use:
+ addition
 subtraction
* multiplication
/ division
^ exponentiation
sine (sin)
cosine (cos)
natural logarithm (ln)
tangent (tan)
arctangent (atan)
arcsine (asin)
arccosine (acos)
hyperbolic sine (sinh)
hyperbolic cosine (cosh)
hyperbolic tangent (tanh)
The number in expression can be as valid which registers in a habitual look, and complex number which is designated by a symbol i
The request whenever possible to wrap each complex number in parentheses if the first symbol in it is minus(es)
EXAMPLES
(41i)/((52i)+71.2i)
or in more evident look
{tex}(41i)/((52i)+71.2i){/tex}
We receive our inquiry looks as we it and created right at the beginning
calc_i (41i)/((52i)+71.2i)
Result of expression
Valid part0.33707865168539
Imaginary part1.0393258426966
i/(5i)+(4+2.7i)/(3i)/0.2i
We receive
{ tex } i / (5i)+ (4+2.7i) / (3i)/0.2i { / tex }
our inquiry looks so calc_i (i / (5i)) ^2+ (4+2.7i) / (3i)/0.2i
Result of expression the
Valid part 2.0115384615385
Imaginary part 7.5423076923077