Maths Questions Help!

robert12345

I'm doing maths revision and can't seem to solve 4 of the questions from the Maths Text & Tests 4 books on Algebra 1. I would really appreciate if you could help me solve these:



The the questions under me say:For what value of m are the roots… but opposite in sign

And: The roots of the equation… (AND) Find the value of p and the value of q.




In this questions the bottom one is the one I can't solve.

ChemHickey

Q1- Try to isolate 2nrh form S. Wriggle this around so it looks like nr^2h and voila!

Q2- let the roots= a, -a. THIS MEANS THAT THE SUM OF ROOTS = a-a which equals 0
Use this eqn which will get you to find roots easily x^2-[sum of roots]x+[product of roots] or just say that the sum of the roots is -b/a and product = c/a. Using that eqn and knowing that the sum=0 you can easily isolate the m and equate to find unknow.

Q3 Using same principlpes, find a+b and ab. a^2 + b^2 = (a+b)^2 -2ab. This said, you can easily find the answer.

Using the same reasoning as previously, find roots in terms of p and q with the roots 2a +b and a + 2b. the sum = 3a +3b which can be written as 3{a+b) which, you have found in the previous part. Sub in the value of p to find q!

Q4- multiply out brackets! (you should get ab - a.root3 +b.root3 -3)
Let the roots = roots and the whole numbers = whole numbers eg. ab-3=7 and the root3's equal each other (using LHS=RHS Principle)) Isolate either a or b and sub in to find values, ignore the negative value and sub in top find other value!!

Hope I helped (p.s - I had solutions about 4 times as long written out but when i went to post it said i wasn't logged in so i lost it all!! but here ya go anyway!)

If you need more help, dont hesitate to ask and also in any other topics in the paper or whatever ( I got 97% in my christmas exam LC there a few weeks ago and it was a whole paper form mocks etc.. )

robert12345

Thank you so much. I've solved all of them except the very first one where you said to isolate 2nprh from s. I can't seem to get it on its own but thank you very much, if I look over it a few more times I'm sure I'll find it.

ChemHickey

robert12345 wrote: »

Thank you so much. I've solved all of them except the very first one where you said to isolate 2nprh from s. I can't seem to get it on its own but thank you very much, if I look over it a few more times I'm sure I'll find it.

Ok. to change 2πrh to πr^2h, you have to divide by 2 and multiply by r? once you know that and have rearranged the first eqn ( say s = x + y; you could rearrange that to say y=s -x ) you can apply the r/2 division on each side to allow yourself to finish off with v on left and some eqn thing on right.

robert12345

Thank you, I finally got that one too. I'll be starting Algebra 2 and I might need some help on that. Also I checked the Maths Ireland website and it helped me solve a lot of these.

Sorry for the late reply!