In the following exercise, use a change of variables to show that each definite integral is equal to zero. Question 311

1 - 2t dt 309. ( 1+ ( 1 - 2 )? 310. 311. (1- t)cos(nt ) dt O 3x/4 312. sintcostdt 313. Show that the average value of [a, b] is the same as the average val interval [a, 2 for c > 0. 314. Find the area under the graph between t = 0 and t = x where fixed, and evaluate the limit as * 315. Find the area under the graph