The Student Room Group

a level maths

how does tan(Ο€ - Ο€/6) = -tan(Ο€/6)
Reply 1
Try put pi and pi/6 into the formula
Reply 2
Original post by Appazap
Try put pi and pi/6 into the formula

i still don't understand
Original post by man111111
i still don't understand


They're called compound angle formulas. Watch videos to understand them. :smile:
Reply 4
Original post by rohit_rocks10
they're called compound angle formulas. Watch videos to understand them. :smile:


is this core 4
Reply 5
Original post by man111111
is this core 4


its C3 in OCR.

all you do is assume Alpha=pi and Beta=pi/6

then put these values into the bottom equation. But i suggest that you do watch youtube videos on it, just to get a better understanding :h:
(edited 6 years ago)
Reply 6
Original post by Appazap
its C3 in OCR.

all you do is assume Alpha=pi and Beta=pi/6

then put these values into the bottom equation. But i suggest that you do watch youtube videos on it, just to get a better understanding


ur answer doesn't give tan(Ο€ - Ο€/6) = -tan(Ο€/6)
Original post by man111111
is this core 4


I do CIE A-Levels, so I'm not too sure about that. But they're pretty straightforward. This should help. :smile: https://m.youtube.com/watch?v=Pf2aeK21wCo
Reply 8
Original post by man111111
ur answer doesn't give tan(Ο€ - Ο€/6) = -tan(Ο€/6)


yes it does as tan Ο€=0
Reply 9
Original post by Appazap
yes it does as tan Ο€=0


what is this topic called and do u know if it is in the core 4 exam for AQA
Original post by man111111
how does tan(Ο€ - Ο€/6) = -tan(Ο€/6)


You don't need any compound angle formulae for this.

You should know that tan repeats every pi radians.

So, tan⁑(Ο€βˆ’Ο€/6)=tan⁑(βˆ’Ο€/6)\tan (\pi-\pi/6)= \tan (-\pi/6)

And tan is an "odd" function, i.e. tan(-x) = - tan(x)

Apply that to the above and we have βˆ’tan⁑(Ο€/6)-\tan (\pi/6)
Draw a quadrant or use the graph, just need some tangent knowledge
Original post by Hammad(214508)
Draw a quadrant or use the graph, just need some tangent knowledge

It's based on the period of the tan function, it repeats every 180 degrees / pi radians therefore if you add or subtract pi from any value of theta (the angle inputted into the tan function), the value you return is equivalent.

Quick Reply

Latest