SOLUTION: For each of the following expressions, calculate the value of x which gives y a stationary value.
Determining whether this value of y is a minimum or a maximum. Give your answers
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Determining whether this value of y is a minimum or a maximum. Give your answers
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Question 1194169: For each of the following expressions, calculate the value of x which gives y a stationary value.
Determining whether this value of y is a minimum or a maximum. Give your answers correct to 3 significant figures where necessary.
a) y = x^2 + (2x-1)^2
b) y = 2πx - (x-2)^2 Answer by Boreal(15235) (Show Source):
You can put this solution on YOUR website! y=x^2+(2x-1)^2
y'=2x+2(2x-1)*2=2x+8x-4=10x-4
set that equal to 0
10x=4
x=0.4
2nd derivative is 10 and is always positive so this is a minimum
alternative way into expand function to x^2+4x^2-4x+1=5x^2-4x-1
find vertex by x=-b/2a=-4/-10 or +0.4
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y'=2 pi-2(x-2)=2pi-2x+4
set equal to 0
2x=2pi+4
x=2+pi or 5.28
y''=-2, and this will be a maximum.
