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If #f(x) = x^2- 2#, how do you find expressions for f(-x)?

Answer 1

Genesis Allen

To find the expression for ( f(-x) ) when ( f(x) = x^2 - 2 ), substitute (-x) for (x) in the function:

[ f(-x) = (-x)^2 - 2 ]

[ f(-x) = x^2 - 2 ]

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Answer 2

Eli Assouline

#f(-x)=x^2-2=f(x)#

#f(-x)=(-x)^2-2=x^2-2#

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Answer 3

Savannah Anderson

see solution process below;

I think you mean't, #f^-1(x)# which is the inverse of #f(x)#

But if its, #f(-x)# it should be #-(x^2 - 2)#

Thus,

#f(x)=x^2- 2#

#f(-x)=-(x^2-2)#

#f(-x) =-x^2+ 2 or 2 + x^2#

But if its #f(x)^-1#

Let, #f(x)= y#

#y = x^2 - 2#

Making #x# the subject of formula;

#x^2 - 2 = y#

#x^2 = y + 2#

#x = sqrt(y + 2)#

Consequently,

#f(x)^-1 = sqrt(x + 2)#

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.