Answer:
0.2397
Step-by-step explanation:
Given data:
fX(x) = Cxe^(−x/2) if x >0 0 otherwise, where C > 0 is some constant.
The probability that the system functions for at least 5 months
= 0.2397
attached below is a detailed solution
Next time make it more easyer
Answer : 
(1) 
Use FOIL method to mulitply (3x – 5)(3x – 5)

(2) 
Use FOIL method to mulitply (3x - 5)(3x + 5)

(3) 
Use FOIL method to mulitply -(3x + 5)(3x + 5)

(4) 
Use FOIL method to mulitply -(3x + 5)(3x - 5)

So equation 2 is true
Answer:
5/7
Step-by-step explanation:
Simplify by finding common factors and dividing both the numerator and denominator by it.
40/ 56 = 20/28(divided by 2) = 10 / 14 (divided by 2) = 5/7 ( divided by 2)
Hope this helps.
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