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Help with C2 Trigonometric functions please

ImageUploadedByStudent Room1397315146.262853.jpg

It is question 3. So far I have done this, but I do not know what to do now.

ImageUploadedByStudent Room1397315193.576541.jpg

Thanks

Posted from TSR Mobile

Reply 1

username1258398

I would suggest drawing a graph of y = tanx from -pi to pi. You can then draw two lines on it, y = root(1/3) and y = -root(1/3). Use the periodic nature of tan to then find the intersections. :smile:

Or, you could just use the fact that tan(x + pi) = tan(x) to find the other solutions in the interval.

(edited 10 years ago)

Reply 2

BabyMaths

Original post by Efemena15

It is question 3. So far I have done this, but I do not know what to do now.

ImageUploadedByStudent Room1397315193.576541.jpg

Thanks

Posted from TSR Mobile

Good so far.

Just add pi to -pi/6 to get 5pi/6

Also subtract pi from pi/6 to get -5pi/6.

Reply 3

Inevitable

Just add/subtract

pi

(because of symmetry) to the principle values obtained for tan

(edited 10 years ago)

Reply 4

Efemena15

Original post by BabyMaths

Good so far.

Just add pi to -pi/6 to get 5pi/6

Also subtract pi from pi/6 to get -5pi/6.

Original post by Inevitable

Just add/subtract

pi

(because of symmetry) to the principle values obtained for tan

Ok, thanks guys, but why do I add/take away pi. I'm trying to practice using the CAST diagram, so if you could explain it like that, that would be helpful.

Thanks

Reply 5

BabyMaths

Original post by Efemena15

Ok, thanks guys, but why do I add/take away pi. I'm trying to practice using the CAST diagram, so if you could explain it like that, that would be helpful.

Thanks

because