Math destroyer test twelve question twenty eight

[510586]

Can someone show their work for this? The answer is E but I am not sure how to get there

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[DAT Destroyer]

Can someone show their work for this? The answer is E but I am not sure how to get there View attachment 194879

 

[510586]

View attachment 194881

Oh shoot I'm a fool I thought it was (1+a)/(1-a) for some reason. Thanks!

 

[510586]

View attachment 194881

Is this answer a typo for 38 test 12? Why isn't the x+2 in parenthesis? Like 1-(x+2)

 

[byahnoob]

Is this answer a typo for 38 test 12? Why isn't the x+2 in parenthesis? Like 1-(x+2)View attachment 194883

PHAT FINGER HA!

 

[510586]

PHAT FINGER HA!

 

[byahnoob]

 

[neoking77]

It should technically be

f(1-x) = (1-x) + 2
which simplifies to
f(1-x) = 1-x+2
f(1-x) = 3-x

So the bootcamp answer just took a shortcut and didn't bother putting in the paranthesis. The end result is the same.

 

[510586]

It should technically be

f(1-x) = (1-x) + 2
which simplifies to
f(1-x) = 1-x+2
f(1-x) = 3-x

So the bootcamp answer just took a shortcut and didn't bother putting in the paranthesis. The end result is the same.

Why is it not 1-(x+2)? If fx=x+2 shouldn't f(-x)=-(x+2)?

 

[neoking77]

Why is it not 1-(x+2)? If fx=x+2 shouldn't f(-x)=-(x+2)?

We're given f(x-1) = x+1
then f(x) = x+2
Remember f(x) means you're replacing whatever's in f(x) into the x value. Try putting the first one back into the equation
f(x-1) = (x-1) +2 = x-1 +2 = x+1

f(-x) = (-x) +2 = -x+2

f(1-x)= (1-x) + 2 = 1-x+2 = 3-x

 

[DAT Destroyer]

(x-1)=x+1. f(x-1+1)=x+2. Then f(x)=x+2.
To find f(1-x) we will first find f(-x) then add 1. f(-x)= -x+2 then f(-x+1)=f(1-x) = -x+2+1 = 3-x

 

[510586]

(x-1)=x+1. f(x-1+1)=x+2. Then f(x)=x+2.
To find f(1-x) we will first find f(-x) then add 1. f(-x)= -x+2 then f(-x+1)=f(1-x) = -x+2+1 = 3-x

Oh yea negative sign only affects the x right? Think that's what I was confused on

 

[510586]

We're given f(x-1) = x+1
then f(x) = x+2
Remember f(x) means you're replacing whatever's in f(x) into the x value. Try putting the first one back into the equation
f(x-1) = (x-1) +2 = x-1 +2 = x+1

f(-x) = (-x) +2 = -x+2

f(1-x)= (1-x) + 2 = 1-x+2 = 3-x

Thank-you