(1 point) Book Problem 15 The following limit lim 2 x,- cos(x,-)Ax, [0, 21:] nmo i=1 is equal to the definite integral fab f(x) dx where a = , b = , and f(x) = (1 point) The following sum 6+2 6+ 18 In (2) + 2 + ( 6+ 7 ) 2 + ( 6 + 18 ( i ) + . + 2+ ( 6+ 20 ) (2 ) is a right Riemann sum for a certain definite integral of(x) dx using a partition of the interval [6, b] into n subintervals of equal length. Then the upper limit of integration must be: b = and the integrand must be the function f(x) =