# I don't understand this integral

0kelvin
What did the teacher meant with this:

$$\int_{a}^{b} f(t)i + g(t)k dt$$

The two functions, a and b are all given. What is it to integrate a vector? From analytical geometry I know that something in the form of i + j + k is a vector.

$$\int_{a}^{b} f(t)i + g(t)k dt$$
Just integrate term by term. The i and k are the unit vectors ##\hat i## and ##\hat j##. It probably makes more sense to write the integral as $$(\int_{a}^{b} f(t)dt) \hat i +(\int_{a}^{b} g(t) dt) \hat k$$