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For each positive integer n, let pn be the following inequality 2 raised to the nth power less than the factorial of n plus 1.
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In part a we talk about what is p2 and if that statement is true.
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In part b we talk about what is pk.
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In part c what is pk plus 1.
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In part d in a proof by mathematical induction that this inequality holds for every integer n greater than or equal to 2 what must be shown in the inductive step.
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So let's see part a what is p2.
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So remember here the statement in this case an inequality depends on the value of n.
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So we talk about p of n for a positive integer n refers to this inequality.
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In other words the argument let's say like that of the proposition p the argument n will be the exponent of 2 on the left hand side of the inequality and will be the value for which we add 1 and then take the factorial of that sum.
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So to have to find p2 we only replace n by 2 in this inequality right here.
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So we get 2 raised to the second power because n equal 2.
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The argument will be the exponent of 2 so it's 2 raised to the second power or 2 square less than 2 which is n plus 1 factorial of that.
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So we'll get 2 square less than 2 plus 1 factorial that's the inequality we get when n equal 2.
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And that's the same as 2 square is 4 on the left less than and we have 3 factorial on the right and that's equivalent to 4 less than if we calculate 3 factorial is 3 times 2 times 1 is 6.
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So this is p2 4 less than 6 and i'm going to say which is the correct options because you have been given options you have 5 options and the correct options is the third from top to bottom.
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So third option from top to bottom...