D Question 1 1 pts Consider the indefinite integral / x . Vx2 + 9 dx This can be transformed into a basic integral by letting a. u =[answer1] b. du = dx [answer2] c. Performing the substitution yields the integral du [answer3] Use math editor to answer 1, 2, and 3. Get help: Video Get help: Video Edit View Insert Format Tools Table 12pt V Paragraph B I U A & TV : 898D Question 2 1 pts Consider the indefinite integral / * 4 ( x5 - 4 ) s dx This can be transformed into a basic integral by letting a. u =[answer1] b. du = _ dx [answer2] c. Performing the substitution yields the integral du [answer3] Use math editor to answer 1, 2, and 3. Get help: Video Get help: Video Edit View Insert Format Tools Table 12pt V Paragraph B I U A & TV :Question 3 1 pts Evaluate the integral J x(x8 -4) 13 by making the appropriate substitution: u = [answer1] J x (x8 - 4) 15 dx = + C [answer2] Note: Your answer should be in terms of x and not u. Use math editor to answer 1 and 2. Get help: Video Get help: Video Edit View Insert Format Tools Table 12pt \\ Paragraph B I U A & V T V ...D Question 4 1 pts Evaluate the integral fxV13 + x3 dx = + C Get help: Video Get help: Video 0 2 ( x3 + 10) 3 0 - ( x2 + 8) 3 02(x3 + 13) 2 0 ( x 3 - 10) 3\fO 2 . ( 5 + 1 ) 2 - 10 . ( s + 1 ) = Question 6 1 pts Use a change of variables to evaluate the definite integral. LuxV 1 - x2 dx = O - 1 O - 1/2 O -1/3 O - 1/4 Question 7 1 pts F4 FOQuestion 7 1 pts A tumor is injected with 0.5 grams of lodine, which has a decay rate of 1.55% per day. Write an exponential model representing the amount of lodine remaining in the tumor after t days. Find the amount of lodine that would remain in the tumor after 40 days. Round to the nearest tenth of a gram. 1. Model: f (t) = _ [ Select ] a) 0.5(0.0155) or 0.5e-0.8792t b) 0.5(0.2583) or 0.5e-0.2583t c) 0.5(0.9845)' or 0.5e-0.0156t Il Remaining after 40 days: grams [ Select ]Question 8 1 pts A scientist begins with 250 grams of a radioactive substance. After 240 minutes, the sample has decayed to 31 grams. To the nearest minute, what is the half-life of this substance? minutes To find the half-life, solve for t in the equation: 31 = 250 300 31 250 31 240 log ! 250 240 t = log 31 250 t ~ 80 In (2) Alternatively, we can solve this by using the formula A = Ane. The half life will be t = k Solve for k: A = Anekt 31 = 250ek -240 31 = ek.240 250 In 31 250 = k 240 k~-0.008731 240 log 1 250 240 t = log1 31 250 t ~ 80 In(2) Alternatively, we can solve this by using the formula A = Ane. The half life will be t = k Solve for k: A = Aoekt 31 = 250ek -240 31 = k-240 250 In 31 250 k 240 k ~ -0.0087 So the half-life is: In(2) ~80 -0.0087 O 20 O 40 O 60 O 80 DII F5 F8 F9 F3 F4 F6 F7
