## monroe17 Group Title trapezoidal rule of integral from 0 to 1 of e^(-6x^2)dx n=4 I got 2.016753867... and it says it's wrong. I split it up as.. delta x/2=1/8 x_0=0 x_1=0.25 x_2=0.50 x_3=0.75 x_4=1 help? one year ago one year ago

1. monroe17 Group Title

nevermind :) got it!

2. monroe17 Group Title

I inputted the function wrong..

3. campbell_st Group Title

so if you draw it I've calcuated the function values and they are on top of the offset. |dw:1359660333907:dw| and from here you can just apply the formula for area of each trapeziod then sum the areas... I've always hated the formula.

4. campbell_st Group Title

but if you want to use the formula you would have $\int\limits_{0}^{1}e^{-6x^2} dx \approx \frac{0.5}{2}[1 + 2 \times 0.687289 + 2 \times 0.22313+ 2 \times 0.034218 + 0.002479]$ and its just a case of evaluating.

5. campbell_st Group Title

oops should be $\frac{0.25}{2}$ at the start

6. campbell_st Group Title

i got 0.361469

7. monroe17 Group Title

yeah I figured it out. Thanks.