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FP1 June 2016 Edexcel Exam Paper Question 7

Question7. A complex number z is given by z = a + 2i where a is a non-zero real number. (a) Find z2 + 2z in the form x + iy where x and y are real expressions in terms of a. (4) Given that z2 + 2z is real, (...
JR
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You have three keys in your pocket which you extract in a random way to unlock a lock. Assume that exactly one key opens the door when you pick it out of your pocket. Find the expectation value of the number of times you need to pick out a key to unlock.

Let X be the random variable for this question. P(X=x) = 1/3 for all x. When X=x, we have that it took x times for us to retrieve the correct key.Thus, we have the infinite sum 1/3 + 2 2/3 1/3 + 3*(2/3)^2 1/...
NO
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What's the best way to solve projectile problems in Mechanics?

Getting a complicated problem of a mass being projected at a weird angle can seem daunting at first but these problems can be solved easily by breaking them down into two simpler problems.Using trigonometry,...
OA
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Solve the second order ODE, giving a general solution: x'' + 2x' - 3x = 2e^-t

First find an auxiliary equation, for the complimentary function:m^2 + 2m - 3 = 0, (m+3)(m-1)=0m=1 or m=-3So the complimentary function is: x= Ae^t + Be^-3tFor the particular integral (PI), let x = Ue^-tthen...
IF
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I do not understand this topic and particularly this example. In the class the result was found out but I still do not get it. How did the teacher came up with this outcome?

Firstly please show me what was the topic and the example in class. Given the topic I will provide the answer and the easiest way to complete it. For example, let's say the student had to solve the equation ...
MF
2923 Views