In the first space, m = ab 2 = 4 is obtained from Pythagorean theorem.

The second empty, 400. Using the knowledge of vectors, it is deduced that vectors are inconvenient to type, and the following are the ideas:

Let BP=tBC (vector), then CP=( 1-t)CB. Then use AB and AC for BC and CB.

You can get the expressions of BP and CP, because AP=AB+BP (vector), so you can also get the expression of AP, and then you can do it.

When they are substituted into the expression of m, they can be finally simplified to AB^2, so the total * * * is100ab 2.

(mainly want to express them as AB, AC relationship)