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1. Hi all I have worked on this question and cannot see how to achieve the final step could someone please help me from where I have got up to?

I started off changing ID to cot^2x= K-4/3

I then inverted to get tan^2x = 3/K-3 to get the K-4 as denominator but how do you get the K-1 part? I saw I can change the tan^2x to sec^2x +1 but I am a K missing!
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2. (Original post by MLW12345)
Hi all I have worked on this question and cannot see how to achieve the final step could someone please help me from where I have got up to?

I started off changing ID to cot^2x= K-4/3

I then inverted to get tan^2x = 3/K-3 to get the K-4 as denominator but how do you get the K-1 part? I saw I can change the tan^2x to sec^2x +1 but I am a K missing!
.
3. (Original post by B_9710)
.

Hi thankyou for the reply yea its this bit I just cant see how does K-1 form please forgive me I cant quite get it from this.
4. (Original post by MLW12345)
Hi thankyou for the reply yea its this bit I just cant see how does K-1 form please forgive me I cant quite get it from this.
Think about how you can rewrite the 1 so you get a common denominator
5. (Original post by MLW12345)
Hi thankyou for the reply yea its this bit I just cant see how does K-1 form please forgive me I cant quite get it from this.
3/(k-4) + 1 = 3/(k-4) + (k-4)/(k-4), since anything divided by itself is 1.
Now since the fractions have the same denominators, we can just add the numerators to get (3+k-4)/(k-4) = (k-1)/(k-4),
as required.
6. (Original post by HapaxOromenon3)
3/(k-4) + 1 = 3/(k-4) + (k-4)/(k-4), since anything divided by itself is 1.
Now since the fractions have the same denominators, we can just add the numerators to get (3+k-4)/(k-4) = (k-1)/(k-4),
as required.
Thank you everyone. I forgot to post the reply understood to +1 (k-4)/(k/4)to get common denominator fantastic thank you!!

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