# Arc length multivariate calc

here is the problem, and I cant seem to get very far,

compute the length of r(t) = <3t, 4cost, 4sint> from t=0 to t=1

i know the formula is integral from 0 to 1 of length of r'(t)

but I keep coming up with 5, and it doesnt seem right, can someone please confirm or deny this. Thanks