Scientific Calculator

Description of Scientific Calculator

A price-free and ad-free calculator could do integral, summation and product.
In real world, most functions cannot be integrated by Newton-Leibniz formula. But sometimes an approximation solution is necessary, so we using a numerical method to approximate the solution. With this app, you could enter whatever function you want. So does summation and product fragment.
Tips:
1.The keyboard is scrollable, if you cannot find the certain button, try
scrolling up or down.
2.The variable x and i in functions are created by the buttons at the bottom of keyboard.
3.When doing a multiplication * is a must, 3*sin(x) is allowed while 3sin(x) is not recognized.
4.Using brackets wisely, you could build a complicated function.
5.It may takes a few seconds to do an integral or summation, time may vary by different phone types and the complexity of the functions.
6.To enter a start or end integer of an integral, click the bottom or top button.