Maths year 11

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Ok, this is the easiest way but we will try another.
Find $\displaystyle \int \text{cosec } x \ dx$ using the substitution $t=\tan (\frac{1}{2}x)$.

You're slowly turning a Y10 thread into a Y13 one.

Fine. I will delete my posts. You as well though, you posted an FP4 question yesterday.

You didn't have to delete them; just stop posting more, there are other threads where challenging problems can be discussed.

God forbid your notation. What the hell is $\frac{dy}{dx}(\frac{1}{cosx}) .dx$ even supposed to mean? Where's the y? Just no.

So then? :/

This was so Challenging.


Posted from TSR Mobile

Likewise with the bottom row. It wouldn't make sense for 15x-6 to be 9x because 6 is not a multiple of x.

Think of it this way:
15x-6x would be 9x because you can always factor out an x from both 15 and 6, leaving you with x(15-6) where you can just take 6 away from 15 as they are not multiples of x anymore, thus leaving you with 9x.
For 15x-6, you cannot factor out any x's because one has it and one doesn't so it wouldn't make sense.

This is really basic, you'll get used to this pretty fast.

yeah sorry i always just write dy/dx but to make it clear what i was doing i wrote d(1/cosx)/dx but i always write dy out of habbit cos im lazy and prefer just doing dy/dx

This was the last question of this past paper and can you give a few examples on these type of questions after we've found the answer to this xx

Posted from TSR Mobile

I'll give you some quadratics to work with, sure.

It's 15x-6, doesn't get any simpler than that.

What's the next step

I found this the hardest! Feel like giving up on this question.

Posted from TSR Mobile

No problem, its only a matter of multiplying out the brackets and adding. Here's the full solution to show you what they want:



Posted from TSR Mobile

Thank you )

Can you give me a few questions to work on as you might be able to tell from the questions what part I'm weak on


Posted from TSR Mobile

I think you're pretty good with the angles at this point, I only see that you can improve perhaps on volumes of shapes and expanding brackets. Let's do a similar one just slightly easier as not all sides are in terms of x:

so first I split the shape in two.



Posted from TSR Mobile

Yep, now label the sides of each rectangle.

But I don't know the sides

Like 15 - X will give me the bottom side but I don't know how to find X.



Posted from TSR Mobile

15-x will indeed give you the bottom side, use it. Don't worry about x as we will find it at the very end. This question firstly wants us to get the area of the whole shape in terms of x before we solve for it.