Melody

I do not know radio.  In theory at least I think there are infinitely many primes BUT

You have taken this a step further - I am not so sure your 'yes' would stand up to close scrutiny.  

Thanks Bertie,

Sorry 315,

Bertie or 315, can you try to explain to me the method that you have used? 

(Just the first one for starters)

I have not obtained the identity yet .

I did check your formula.  It seems to me that the 2i needs to be in brackets.  

2x+(x-10)+(2x+15)=180

5x+5=180

5x=175

x=35

The biggest angle is 2x+15=2*35+15=70+15=85 degrees

With your fingers

JJ, firstly, it can not be a question because there is not question mark!

so be careful about who you call names.

Secondly, this is a international forum so this 'question' has no meaning for most people who will read it.

Hi  315  

I do not know WHAT you are doing BUT the second one is NOT correct.

This is how I would do it.

$$\\\int\;CotxCosec^4x\;dx\\\\
=\int\;\frac{Cosx}{Sinx}\frac{1}{sin^4x}\;dx\\\\
=\int\;\frac{Cosx}{Sin^5x}\;dx\\\\
=\int\;CosxSin^{-5}x\;dx\\\\
=\frac{Sin^{-4}x}{-4}+c\\\\
=\frac{-Cosec^{4}x}{4}+c\\\\$$

thanks anon,

You are right except that the m^3 cancel out :))

Try watching this

Thanks Zekkuno, and welcome to the forum