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C1 Indices Help

Please may I have some help on the following two questions; Question 11 and question 7 on the second picture. Thanks
Reply 1
Original post by candyhearts
Please may I have some help on the following two questions; Question 11 and question 7 on the second picture. Thanks


For 11 take it a stage at a time - for example, can you see how to simplify the first factor in the numerator?
Reply 2
Original post by candyhearts
Please may I have some help on the following two questions; Question 11 and question 7 on the second picture. Thanks


And for 7 replace m and n inside the brackets with their equivalents in terms of a, then combine indices and simplify. Equate both sides as powers of a and you should be done!
Reply 3
7)
[br]a2=myznxz[br]a^2 = m^{yz}n^{xz}

Substitute in m and n.

a2=axyzaxyz[br]a2=a2xyz[br]2=2xyz[br]xyz=1a^2 = a^{xyz}a^{xyz}[br]a^2 = a^{2xyz}[br]2 = 2xyz[br]xyz = 1

11) xc2cca+a x^{c^2 - c - ca + a} ?
(edited 10 years ago)
Reply 4
Original post by davros
And for 7 replace m and n inside the brackets with their equivalents in terms of a, then combine indices and simplify. Equate both sides as powers of a and you should be done!


Thankyou, I managed to do number 7. Having a little difficulty with 11, this is what I've done so far
Reply 5
Original post by GeneralOJB
7)
[br]a2=myznxz[br]a^2 = m^{yz}n^{xz}

Substitute in m and n.

a2=axyzaxyz[br]a2=a2xyz[br]2=2xyz[br]xyz=1a^2 = a^{xyz}a^{xyz}[br]a^2 = a^{2xyz}[br]2 = 2xyz[br]xyz = 1

11) xc2cca+a x^{c^2 - c - ca + a} ?

Thankyou, for number 11, Im getting xa22ac+c2+ac x^{a^2 - 2ac + c^2 + a - c} Please could you perhaps point out where I've gone wrong
Reply 6
Original post by GeneralOJB
7)
...


Please don't post full solutions - it's against the forum guidelines, and it doesn't give the OP chance to have a go with hints provided.
Reply 7
Original post by candyhearts
Thankyou, for number 11, Im getting xa22ac+c2+ac x^{a^2 - 2ac + c^2 + a - c} Please could you perhaps point out where I've gone wrong


You've got your denominator wrong - you've somehow got (xa)c(x^a)^c turning into xa2x^{a^2} in the factor you divide by, so you've lost an a2a^2 that should have been there and gained another term in the exponent that should be there!!
Reply 8
Original post by davros
You've got your denominator wrong - you've somehow got (xa)c(x^a)^c turning into xa2x^{a^2} in the factor you divide by, so you've lost an a2a^2 that should have been there and gained another term in the exponent that should be there!!


How did I not spot that, thank you very much :smile: (Unfortunatley I cant seem to give you rep), but I appreciate you saving me from spending ages on those questions.
Reply 9
Original post by candyhearts
How did I not spot that, thank you very much :smile: (Unfortunatley I cant seem to give you rep), but I appreciate you saving me from spending ages on those questions.


No problem - for what it's worth that Q11 is one of the nastier indices questions I've seen!
Reply 10
Original post by davros
No problem - for what it's worth that Q11 is one of the nastier indices questions I've seen!


That makes me feel a little relieved :smile:
Original post by candyhearts
Please may I have some help on the following two questions; Question 11 and question 7 on the second picture. Thanks


nasty questions. where do you get those? i would like to crack on with them.
Reply 12
Original post by CoolRunner
nasty questions. where do you get those? i would like to crack on with them.

This book
http://www.amazon.co.uk/gp/aw/d/1902214455

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