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## #1 2008-03-16 01:06:59

q8boy
Guest

### trigo (a-level)

can someone solve this for me?

dy/dx = 2tanx + 2xsec²x

find the gradient at x = pi/4

## #2 2008-03-16 01:09:18

q8boy
Guest

### Re: trigo (a-level)

i get the 2tanx = 2 but 2pi/4(sec²pi/4) = ??

## #3 2008-03-16 03:50:00

Daniel123
Member
Registered: 2007-05-23
Posts: 663

### Re: trigo (a-level)

Last edited by Daniel123 (2008-03-16 04:29:00)

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## #4 2008-03-16 03:51:35

LuisRodg
Real Member
Registered: 2007-10-23
Posts: 322

### Re: trigo (a-level)

Finding the gradient just means finding the slope or the value of the derivative (dy/dx) at the specified x value.

So if you have:

This is the same as just plugging in the x:

Last edited by LuisRodg (2008-03-16 04:02:03)

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## #5 2008-03-16 03:54:21

Daniel123
Member
Registered: 2007-05-23
Posts: 663

### Re: trigo (a-level)

Luis, you need to use lower case \pi.

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## #6 2008-03-16 04:02:55

LuisRodg
Real Member
Registered: 2007-10-23
Posts: 322

### Re: trigo (a-level)

Thanks Daniel. I *always* have problems with this latex lol!

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q8boy
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thanks guys

## #8 2008-03-16 04:28:06

LuisRodg
Real Member
Registered: 2007-10-23
Posts: 322

### Re: trigo (a-level)

No problem.

What is this "a-level" you put in the topic?

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## #9 2008-03-16 04:34:43

Daniel123
Member
Registered: 2007-05-23
Posts: 663

### Re: trigo (a-level)

British Secondary School (High School) System:

AS and A level are two different levels of qualifications. They are completed in the last two years of Secondary School, before University.

Generally,

Ages 16-17: AS level
Ages 17-18: A level

Students usually choose 4 AS level subjects, and then the same 4 (or they often drop one and take 3 of the 4) for A level.

Last edited by Daniel123 (2008-03-16 04:46:03)

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## #10 2008-03-16 04:50:24

LuisRodg
Real Member
Registered: 2007-10-23
Posts: 322

### Re: trigo (a-level)

Does this constitute an "Advanced" program or is this the general educational setup for everyone?

I live in the US, and back when I was in High School I was part of the IB program (International Baccalaureate) which in fact is an European program and it had a similar setup in the sense that you chose 3 HL (Higher Level) and 3 SL (Standard Level) classes. But this was in the same year.

Last edited by LuisRodg (2008-03-16 04:55:45)

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## #11 2008-03-16 05:05:14

Daniel123
Member
Registered: 2007-05-23
Posts: 663

### Re: trigo (a-level)

Students are not required (yet) to stay in school to do these qualifications.

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## #12 2008-03-16 07:32:26

Daniel123
Member
Registered: 2007-05-23
Posts: 663

### Re: trigo (a-level)

Out if interest, do you pronounce your name "loois" or "looeey"?

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## #13 2008-03-16 12:01:12

LuisRodg
Real Member
Registered: 2007-10-23
Posts: 322

"loois"

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## #14 2017-03-17 16:24:01

Monox D. I-Fly
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Registered: 2015-12-02
Posts: 727

### Re: trigo (a-level)

Daniel123 wrote:

Out if interest, do you pronounce your name "loois" or "looeey"?

"Luis" can be pronounced as "Looeey"?

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