ATAR Notes: Forum
HSC Stuff => HSC Maths Stuff => HSC Subjects + Help => HSC Mathematics Advanced => Topic started by: Jefferson on March 16, 2019, 04:59:51 pm
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Hi everyone,
For this question, I broke the function into 2 curves and have the larger volume subtract the smaller.
I can't seem to get the answers provided by the textbook, which is 215pi/6 u^3.
Please show me how this question should be done.
Thank you.
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Hey!! ;D I am not sure if your answer is correct or not but I can tell you how the text book obtained their answer.
The text book only used the "Right side" of the graph:
Which results in:
And then what the answers go toward is that:
This results in:
which gives the final number of:
However, we forgot to multiply the pi so we get:
I am not sure this helped a lot but I hope it at least tells you what the answers did!!! Sorry if it didn't help :'(
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Hey! Thanks heaps to David for the working above ;D assuming that's what the textbook has done, they've done that because they've wanted you to assume that the volume starts at the y-axis and stops as soon as you hit the curve - Which indeed happens on the right hand side of the graph.
That's a bit of an ambiguous thing to ask though, and indeed, the way you've done it Jefferson is way more interesting a question anyway ;D
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I am not sure this helped a lot but I hope it at least tells you what the answers did!!! Sorry if it didn't help :'(
Hey! Thanks heaps to David for the working above ;D assuming that's what the textbook has done, they've done that because they've wanted you to assume that the volume starts at the y-axis and stops as soon as you hit the curve - Which indeed happens on the right hand side of the graph.
That's a bit of an ambiguous thing to ask though, and indeed, the way you've done it Jefferson is way more interesting a question anyway ;D
Hi,
Thank you both for answering. It did help a lot!
I guess my interpretation of the question was off. Yikes.
Deeply appreciated the worked solution and clarification.
- Jefferson.
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Hi,
Thank you both for answering. It did help a lot!
I guess my interpretation of the question was off. Yikes.
Deeply appreciated the worked solution and clarification.
- Jefferson.
I'd say the question was off, not you! :)