- #1
Calavera
- 7
- 0
Hi there,
I have a math test tomorrow and I have some questions from our books review sets that I haven't been able to solve yet. For now I only have questions on functions and Sequenzes & Series but it's possible that I might ad a few more later during the day. Here it goes...
---Functions---
1) I have the folowing graph, and with its help I'm supposed to find the domain and range. I can easily find the domain, but not the range. I don't actually know how to do it...
http://www.viitanen.se/q1f.gif
2) I plot the graph g(x)=x^2 + 6x + 7
Then I'm supposed to: "explain why g for x ≤ -3 has an inverse function g^-1".
To be honest I don't even know how to start...
3) Given h(x)=(x-4)^2 +3 where x≥3 I'm supposed to find the defining equation of h^-1.
I started on this by chaning the variables (changin place with y and x), and I finaly got it to: y^2 - 8y +16 = x-3. Ok, I can simplyfy it more but what should I do to the y^2? Should I use the abc formula, should I factorize it?
---Sequences & series---
1) Find the first term of the sequence 5, 10, 20, 40 which exceeds 10 000.
I wrote up the formula (5(2^n -1))/1 and plotted it on my gdc, then I got the answer that it was supposed to be U11, and when I put that into my formula and I got a right answer, 10235. The thing is that the key to the book says: "t12=10240"!
2)6000€ is invested, at 7% p.a. What is the compound interest after 5 years if the interest is compounded a) quaterly b) monthly.
I have really tried to solve this several times but haven't succeded. I don't simply know what to do...please help.
Ok, I know that there are a lot of problems but I would be really happy if someone could help me...soon if possible (test tomorrow). Thank you in advance!
I have a math test tomorrow and I have some questions from our books review sets that I haven't been able to solve yet. For now I only have questions on functions and Sequenzes & Series but it's possible that I might ad a few more later during the day. Here it goes...
---Functions---
1) I have the folowing graph, and with its help I'm supposed to find the domain and range. I can easily find the domain, but not the range. I don't actually know how to do it...
http://www.viitanen.se/q1f.gif
2) I plot the graph g(x)=x^2 + 6x + 7
Then I'm supposed to: "explain why g for x ≤ -3 has an inverse function g^-1".
To be honest I don't even know how to start...
3) Given h(x)=(x-4)^2 +3 where x≥3 I'm supposed to find the defining equation of h^-1.
I started on this by chaning the variables (changin place with y and x), and I finaly got it to: y^2 - 8y +16 = x-3. Ok, I can simplyfy it more but what should I do to the y^2? Should I use the abc formula, should I factorize it?
---Sequences & series---
1) Find the first term of the sequence 5, 10, 20, 40 which exceeds 10 000.
I wrote up the formula (5(2^n -1))/1 and plotted it on my gdc, then I got the answer that it was supposed to be U11, and when I put that into my formula and I got a right answer, 10235. The thing is that the key to the book says: "t12=10240"!
2)6000€ is invested, at 7% p.a. What is the compound interest after 5 years if the interest is compounded a) quaterly b) monthly.
I have really tried to solve this several times but haven't succeded. I don't simply know what to do...please help.
Ok, I know that there are a lot of problems but I would be really happy if someone could help me...soon if possible (test tomorrow). Thank you in advance!
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