How to solve an integral by parts?

How would you solve the mathematics word problem below on ALL parts?

• Rumors are spreading that all the still standing Republicans trying the GOP are going to debate in Cornwall. The ton's 1400 residents have heard the rumor is given by P where P(d)=1400-1400e^-.16d where d is the number of days since the rumor first broke 3 days ago. a.)How many people know about the rumor now? b.)When will 900 people know about the rumor? c.)How many will know about the rumor in another week? d.)Draw graph of P.

• Answer:

  Day >>>>>>>>>>>>>>> People 0 1400 1400 0 1 1400 1193.001305>> 206.9986954 2 1400 1016.608652>> 383.3913481 3 1400 866.2967485>> 533.7032515 4 1400 738.2093937>> 661.7906063 5 1400 629.0605498>> 770.9394502 6 1400 536.0500404>> 863.9499596 7 1400 456.7917125>> 943.2082875 8 1400 389.2522206>> 1010.747779 9 1400 331.6988622>> 1068.301138 10 1400 282.6551252>> 1117.344875