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Preliminary mathematics marathon (5 Viewers)

SpiralFlex

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Prove
(sin 150 + cos 270 + tan 315 )^2= sin^2 135 cos^2 225

Just wondering is there are faster method then finding the values of both sides then comparing ?
Don't think so, either way, you would still need to convert.









 

Saturn WY15

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Hey Spi, Can u do this question

Solve the equation 6x^4-29x^3+40x^2-7x-12=0, given the product of two of the roots being 2?

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Timothy.Siu

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and then cross multiplying and solving you get:

x = (1 + root5)/2 or (1 - root 5)/2

and then you take the positive one?

is that right?
yep, u can do it like that, but the more obvious way i thought was to say


:) well done.

thats cool, what is the golden ratio? and do you learn it in uni?
Just read the wiki :p http://en.wikipedia.org/wiki/Golden_ratio
I haven't learnt it in uni, although it comes up sometimes, like in that above "continued fraction" representation of the golden ratio.
 
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