TI-86 Help Calculate Definate Integral

[nachiketa1]

I'm trying to calculate a definate integral using the "fnInt" command. It is e^-j*2*pi*t, and I am using (0,1) for "j". But I keep
getting a Data Type Error, when entering fnInt(e^-(0,1)*2*pi*t, t, 1/4, 1/8). Any suggestions?

 

[Scootin159]

I always just graph it & then have it find the integral between 2 points.

 

[nd]

I've never had any success integrating complex functions on my TI-86.

Use an integral table to solve this.

Edit: On second thought -- after actually looking at the function you're trying to integrate -- I don't see why you didn't try this manually already. It's actually a simple integral if you typed it correctly.

"e^(-j) * 2 * pi" is a constant value, and can be pulled out of the integral. So the answer is e^(-j)*2*pi * (.5(1/8)^2 - .5(1/4)^2)

 

[Fandu]

Why not just use the Fundamental Theorm? int(f(x)) = F(B) - F(A)

Where F() is the antiderivative, A is the lower limit, and B is the upper. Pretty easy to solve.

 

[tigerbait]

I just tried plugging it in my Ti-86 a few ways and kept getting the data type error. I guess you can't use complex numbers with the Fnint command