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secondary 4 | A Maths
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Christmas MT
Christmas MT

secondary 4 chevron_right A Maths chevron_right Singapore

ii, iii, iv. I don’t get the concept behind it. (I know min and max value but idk how to apply it for those 3 parts) tyty

Date Posted: 5 years ago
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Eric Nicholas K
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Christmas MT
Christmas MT
5 years ago
Hi tq for replying. For iii how did u get 0 squared tho?
Mathaddict100
Mathaddict100
5 years ago
You knew that when it comes to r-formula concepts,there are two r values (maximum and minimum) of which you denote a negative sign for the minimum and positive sign for the maximum...In this case,the minimum doesn't make a difference as it is still positive the moment you squared it...Well,the qns ask for a maximum..so the nearest r value is 0..Hope this answer your qn...
Christmas MT
Christmas MT
5 years ago
@mathaddict100 oh I see. So if they ask for 1/42+ (r etc)^3 the max value then it wldnt be 0 right. Sry if the qns is a bit stupid I js wna confirm.
snell
Snell
5 years ago
hi,
can u post the qn again?
i can ans :)
Christmas MT
Christmas MT
5 years ago
@snell okay
Mathaddict100
Mathaddict100
5 years ago
Yes..Good Job!.. :) You can see it now...it depends on the power...Notice that even powers gives of a positive sign while odd powers still gives a negative sign.If it is cubic,it will be negative so the overall value will be maximum..It's ok to ask any foolish qn..You're learning..Its better to understand rather than not ask anything at all and keep making mistakes.. :)
Christmas MT
Christmas MT
5 years ago
@mathaddict100 ty for replying! Yea I’m learning hahaha

but like normally they when the r formula isn’t to the power of anything..why is it that the part next to R ( sin(etc) ) speficially must b -1 for min value and 1 for maximum value. Is there a significance behind it? And like why does it change when u add a power. I get the previous explanation but still..
Mathaddict100
Mathaddict100
5 years ago
I guess you understood this already..
Mathaddict100
Mathaddict100
5 years ago
Oops,didn't know you're referring to the last qn...For it to be minimum,the r value should be minimum..not maximum..I didn't do the calculations and thought that the cube value is less than 42..So by mistake,I thought it is maximum overall..
Christmas MT
Christmas MT
5 years ago
Oh, its okay, thank you.