N [ (x2 + 1 ) de 4. Use the limit definition to evaluate 0 You may recall 1+2+3+.... +n n (n + 1) 2 And 12 + 22 + 32 + .... + 12 - 1( n (n + 1) (2n + 1) 6 [ (1 + sin x) dx 0 5. Evaluate 6. Find the average value of the function f(x) = x +1 -2 on the interval x [1,3] and all the values of x in [1,3] for which the function equals this average value