exact value (1 Viewer)

[fullonoob]

how do i find the exact value of tan35, cant form the double angles atm

 

[shaon0]

how do i find the exact value of tan35, cant form the double angles atm

tan((60+45)/3)

 

[han_premium]

tan((60+45)/3)

And how do you do that?

 

[shaon0]

And how do you do that?

There's probably a shorter way than using tan(105/3) but find the expansion of tan3@ and then let @=x/3. You'll get x^3-3Kx^2-3x+K=0 where K=tan(105). And then just use the cubic formula lol. And sub in a hell lot of values.

 

[mirakon]

There's probably a shorter way than using tan(105/3) but find the expansion of tan3@ and then let @=x/3. You'll get x^3-3Kx^2-3x+K=0 where K=tan(105). And then just use the cubic formula lol. And sub in a hell lot of values.

I doubt a hsc level student knows cubic formula. Is it even in the syllabus?

 

[shaon0]

I doubt a hsc level student knows cubic formula. Is it even in the syllabus?

Nah, it isn't lol. I don't think they'll ask such crap questions. They're more likely to ask tan(15)=tan(45-30)

 

[mirakon]

hmmm..... yes I agree. They'd probably just make you apply a single double-angle formula rather than such multi-step questions, espcially if the cubic is as inelegant as the above.

 

[shaon0]

hmmm..... yes I agree. They'd probably just make you apply a single double-angle formula rather than such multi-step questions, espcially if the cubic is as inelegant as the above.

Yeah, only way there'd be a nice solution is if x E Q. And there's isn't one for this cubic.

 

[fullonoob]

i still cant do it with the double angle result, i use the expansion of tan angles over 3 and i dont get the answer still..
lol dw making it over 3 is wrong method
how would you do it? solution please

 

[Drongoski]

how do i find the exact value of tan35, cant form the double angles atm

Where is this question from? I don't think it is easy at all.

 

[shaon0]

i still cant do it with the double angle result, i use the expansion of tan angles over 3 and i dont get the answer still..
lol dw making it over 3 is wrong method
how would you do it? solution please

If there's an exact value for tan(35), i'd like to hear it lol.

 

[ohexploitable]

I don't think there's an exact value...

tan 35 - Wolfram|Alpha

 

[fullonoob]

LOLOL the question wasnt find exact values, dw i got it
was a show question xP

exploitable where do you get these epic animations, lags typing as well

 

[shaon0]

LOLOL the question wasnt find exact values, dw i got it
was a show question xP

exploitable where do you get these epic animations, lags typing as well

But you state: "find the exact value..."

 

[fullonoob]

the question before it was find exact value
i was watching a movie while doing this so looked up and down and didnt read question

 

[fullonoob]

i got a exact value question now
find exact value of tan (pi / 8)
using 1-cos2x / 1+cos2x = tan^2 x
i got the answer but i dont know how to get it into a simpler form, help ^^

root2 - 1 is the answer
i got root (3-2root 2)
yes i know its just a subbing in question, just dont know what to sub

 

[shaon0]

i got a exact value question now
find exact value of tan (pi / 8)
using 1-cos2x / 1+cos2x = tan^2 x
i got the answer but i dont know how to get it into a simpler form, help ^^

root2 - 1 is the answer
i got root (3-2root 2)
yes i know its just a subbing in question, just dont know what to sub

tan(pi/8)=sqrt((2-sqrt(2))/(2+sqrt(2)))
=(2-sqrt(2))/sqrt(4-2) [Multiplying by:sqrt(2+sqrt(2))]
=sqrt(2)(sqrt(2)-1)/sqrt(2)
=sqrt(2)-1