I am an ultra newbie to all this, and I'm learnin in my own free time, so keep it simple plz. I know it is something to do with including <math.h>, which I can do, but then how do I use the functions within it? do I simply have to type num^3 or something and it will work, what about square roots?
I have seen some code on this board for square roots but it looks to be in C, and I'd like C++ (I dont know anything about C so it is difficult for me to understand and learn from)
Thanks for any help
Code:#include <iostream.h> #include <math.h> int main ( ) { double a, b, c; a = 7.0; b = pow( a, 2 ); c = sqrt( b ); cout << a << " squared is " << b << endl; cout << c << " is the square root of " << b << endl; return 0; }
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
If at first you don't succeed, try writing your phone number on the exam paper.
Thanks Salem I can now carry on with that maths program I've been working on, I get £5 from my maths teacher if I make a program that can solve linear, quadratic and cubic equations.
There exist formulae which can solve quadratic and cubic equations. It is mathematically impossible for a simple formula to exist to solve quintic (not sure about quartic) polynomial equations.
If the input is going to be like this, then it should be easy:
If equation is: x^4 + 2x^3 - 9 = 0
Then you input: 1, 2, 0, -9
If you have to be able to solve more complicated ones, then you're in trouble! You'd have to write an equation parser, and then I guess you'd just have to graph it over some massive domain and find intersections with 0, using a binary search to narrow down on the exact X values of the intersections. Of course, that's ignoring imaginary roots. And if your roots are outside the domain, then you have another problem.
Thanks to you too, TerranFury, I was under the impression that cubic equations could only be solved by trial and error, until I went out and looked for a formula. I had written a program for the trial and error method but it wasnt always reliable and was very slow. Now I can do it properly.
I'm not intending to make a program to solve quartic and quintic equations just yet so I should be ok, I'm only just getting started. Win32API is my next step which I'm learning now.
