area of triangle = 1/2(3)(4) = 6 in^2
area of rectangle = 3 x 10 = 30 in^2
area of trapezoid = 1/2(3+5)(2) = 8 in^2
area of the figure: 6 in^2 + 30 in^2 + 8 in^2 = 44 in^2
answer
44 in^2
Let
In order to prove this by induction, we first need to prove the base case, i.e. prove that P(1) is true:
So, the base case is ok. Now, we need to assume and prove .
states that
Since we're assuming , we can substitute the sum of the first n terms with their expression:
Which terminates the proof, since we showed that
as required