## WeBWorK Main Forum

### checking test point sampling

by Joel Trussell -
Number of replies: 0
I recently has a case using a problem that asked the students to reconstruct an aliased sinusoid after sampling. the student's answer was
f1 = 9*cos(340*6*pi*t+1.5708)+10*cos(440*6*pi*t-1.0472);
the correct ansswer is
f2 = 9*cos(340*6*pi*t+1.5708)+10*cos(310*6*pi*t+1.0472);

I changed the code to use limits of [-1/$Fmax,1/$Fmax], where Fmax is the maximum frequncy of the random frequencies in the problem. This works and showed the student's answer in error.