Numerical integration methods for surface integral

Why trapz is giving me negative area?

I need an answer for the program below

Cumtrapz integration drift with time

why do i get error using * ?

integral of indicator function

Simpson method, ezplot (with strings)

Warning: Non-finite result. The integration was unsuccessful. Singularity likely.

Trying to make the plot of potency along Z that is a decaying exponential but it goes straight to zero

Warning: Non-finite result. The integration was unsuccessful. Singularity likely. > In integral2Calc>integral2t (line 131)

how to find a function written as a series

How to define this function?

Is it possible to display a symbolic integral with bounds and function?

Matlab Integration with syntax

Integrating multivariate Gaussian pdf in 4 dimensions

How to fit an integral with more than one variables?

How do I plot an integral which is repeated over an interval?

Romberg integration method with Matlab

Integral and inverse integral

Simulink Integral with variable bounds

Integral2 seems to substitute non-scalar values of variable into integrand. Why?

Numerical integration involving log(exp(f(x))) shows NaN

How to numerically evaluate this singular integral in integral2?

Fitting data to custom integral function

Speed of vpaintegral vs. int+vpa