# Evaluating Expressions for Function Notation

• Nov 9th 2007, 06:33 AM
countryrene
Evaluating Expressions for Function Notation
I need help with two problems please.

1) f(x)=x^2-7x+10
a) find for f(0)
b) find for f(5)
C0 find for f(-2)

2) f(x)=5x-1
a) find for (a-2)

Thanks for anyone's help...........
• Nov 9th 2007, 06:45 AM
kalagota
Quote:

Originally Posted by countryrene
I need help with two problems please.

1) f(x)=x^2-7x+10
a) find for f(0)
b) find for f(5)
C0 find for f(-2)
...........

all you have to do is to replace x with the one inside your parenthesis..
for example, from your function, if i am looking for f(1), then it is equal to (1)^2 - 7(1) + 10 = 4.. now, can you do for your question?

Quote:

Originally Posted by countryrene
2) f(x)=5x-1
a) find for (a-2)

Thanks for anyone's help...........

if it is f(a-2), then just like the one above, just replace x with a-2.. Ü
• Nov 9th 2007, 06:52 AM
topsquark
Quote:

Originally Posted by countryrene
I need help with two problems please.

1) f(x)=x^2-7x+10
a) find for f(0)
b) find for f(5)
C0 find for f(-2)

f(0): Just plug in 0 for x:
$f(0) = 0^2 - 7 \cdot 0 + 10 = 0 - 0 + 10 = 10$

You try the other two.

Quote:

Originally Posted by countryrene
2) f(x)=5x-1
a) find for (a-2)

Again, just plug in a - 2 for x:
$f(a - 2) = 5(a - 2) - 1 = 5a - 10 - 1 = 5a - 11$

-Dan