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1. f is defined by f : x --> e^x +k

1. state the range of f
2. find(ln k)

2. think about the values e^x can take: if necessary, draw the graph. Then work out which values e^x +k can take (this depends on the value of the constant k)
3. The range is the set of values that f can take.

For example, say we have . Since for any value of , we must have , and so is the range. So what is the range here?

For Q2 I think you must have missed out part of the question because we can't find without knowing what is equal to.
4. for the 2nd part, is there any extra context?
5. thanks for all the help so far
question 2 in full:
"f:x --> e^x +k, xER, and k is a positive constant.
find f(lnk)"
6. (Original post by nuodai)
The range is the set of values that f can take.

For example, say we have . Since for any value of , we must have , and so is the range. So what is the range here?

For Q2 I think you must have missed out part of the question because we can't find without knowing what is equal to.
x > k?
7. (Original post by pete.mcfc)
find f(lnk)"
Right! That's not what you said

When you have and you need to find , there are three simple steps you need to follow:
1. Write out the expression for . In this case
2. Replace any occurrence of "x" with "(x)", so here we have
3. Replace what's inside the brackets with the "something"
...then simplify if necessary.

Step #2 isn't really necessary, but it's useful when you're learning how to do these things for the first time (it's easy to make silly mistakes).

(Original post by pete.mcfc)
x > k?
Yup
8. (Original post by nuodai)
Right! That's not what you said

When you have and you need to find , there are three simple steps you need to follow:
1. Write out the expression for . In this case
2. Replace any occurrence of "x" with "(x)", so here we have
3. Replace what's inside the brackets with the "something"
...then simplify if necessary.

Step #2 isn't really necessary, but it's useful when you're learning how to do these things for the first time (it's easy to make silly mistakes).

Yup
haha sorry about that but thanks, rep for you and Mc^3 when I can spread the love

e^(ln k ) + k
do e and ln cancel leaving 2k?
Sorry if I'm being stupid/frustrating
9. they do indeed
10. (Original post by Mc^3)
they do indeed
both legends thanks x

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