Use mathematical induction to prove that the statement is true for every positive integer n.2n > 2n + 2, for n ? 4

What will be an ideal response?


Answers will vary. One possible proof follows.
a). Let n = 4. Then 24 > 2?4 + 2. So, the statement is true for n = 4.
b). Assume S is true for n = k:
 2k > 2k + 2
 Multiply both sides by 2 to obtain:
 2?2k > 2(2k + 2), or
 2k+1 > 4k + 4.
 Re-write the right-hand side as 2(k + 1) + 2k + 2:
 2k+1 > 2(k + 1) + 2k + 2.
 Since k > 0, then 2(k + 1) + 2k + 2 > 2(k + 1) + 2. So,
 2k+1 > 2(k + 1) + 2.
The statement is true for n = k + 1 if it is true for n = k. Furthermore, the statement is true for n = 4. Therefore, the statement is true for all n ? 4.

Mathematics

You might also like to view...

Reverse the order of integration and then evaluate the integral.

A. e25 - 1
B. 5e25 - 130
C.
D. e25 - 

Mathematics

Solve.The profit made when t units are sold,  is given by   Determine the number of units to be sold for which  (a loss is taken).

A. t > 0 B. t = 11 or t = 17 C. 11 < t < 17 D. t < 11 or t > 17

Mathematics

Substitute the value(s) for the variable(s) and then evaluate.(x + 3)2 - 2 ? 5; x = 4

A. 235 B. 39 C. 15 D. 115

Mathematics

Determine whether the graph is the graph of a function.  

A. function B. not a function

Mathematics