Barry is trying to calculate the distance between point e(3, 1) and point f(4, 7). which of the following expressions will he use?

Given that (x-3) is a factor of f(x)=x^3+ax^2-x-6, find a and hence the number of real roots or the equation f(x)=0

Aflagpole broke in a storm. 77 7 meters are still sticking straight out of the ground, where it snapped, but the remaining piece has hinged over and touches the ground at a point 2424 24 meters away horizontally

If sina is 4/5 then find the value of sin3a . with explanation.