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Well, my maths teacher has given me a sheet on surds for "revision" (even though she never taught us it in the first place) and I don't have a clue how to do it. She gave it to us today and its for tomorrow (current time is 22:48)<br />
<br />
The sheet is on <a href="http://www.harrycarlton.co.uk/subjects/maths/gcsehomeworrk/Higher1t30.pdf" target="_blank">http://www.harrycarlton.co.uk/subjec...Higher1t30.pdf</a> the password is "eastleake" and it is page 4 for surds.<br />
<br />
Can anybody help/point in right direction/do something to help me out please?<br />
Its something to do with leaving it in the square root form or something...<br />
<br />
Thanks guys
 

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<div style="margin:20px;margin-top:5px;">
<div class="smallfont" style="margin-bottom:2px;">Quote:</div>
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<div>Originally Posted by <strong>Niko-Time</strong></div>
<div style="font-style:italic;">Well, my maths teacher has given me a sheet on surds for "revision" (even though she never taught us it in the first place) and I don't have a clue how to do it. She gave it to us today and its for tomorrow (current time is 22:48)<br><br>
The sheet is on <a href="http://www.harrycarlton.co.uk/subjects/maths/gcsehomeworrk/Higher1t30.pdf" target="_blank">http://www.harrycarlton.co.uk/subjec...Higher1t30.pdf</a> the password is "eastleake" and it is page 4 for surds.<br><br>
Can anybody help/point in right direction/do something to help me out please?<br>
Its something to do with leaving it in the square root form or something...<br><br>
Thanks guys</div>
</td>
</tr></table></div>
Alright, you'll need a calculator. I assume you have one.<br><br>
It's simple, just enter the problem in the calculator and it pretty much does all the work. So you can get the idea of how it works, I'll do one for you.<br><br><img alt="" src="http://img.photobucket.com/albums/v335/iskate46/untitled-2.jpg" style="border:0px solid;"> is equal to "the square root of 500 minus 3 times the square root of five".<br><br>
When its a number and then the square root sign, and then another number, that means to find the square root of the number on the right and then multiply that times then number on the left. It's simple, it's your "PEMDAS" rule, or order of operations. (Parentheses, exponents, mulitply, divided, add, subtract)<br><br>
Okay, so once you have solved that it's just the square root of 500 minus that other thing you solved. (3 times the square root of 5)<br><br>
If you need any other help, I'll be here for a while lol.
 
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If you have to leave it in the square you form you have to work it around so the numbers inside the root match so:<br>
Root 500 can be broken down into 2 x 2 x 5 x 5 x 5. You can take out a pair of 2's and a pair of 5's. You need to have a pair of them sinces its under a root. After taking it out you are left with a 2 and a 5 on the oustide. Multiply these to get 10 root 5. Then you have 10 root 5 minus 3 root 5 which is 7 root 5. Its hard to explain without paint.<br><br>
Ok Ill try to turn it into steps:<br>
breakdown number in root sign into factors<br>
500 turns into 2x2x5x5x5<br>
Move pairs of factors to the outside, two factors = 1 number outside the root<br>
Remove the pair of 2's and 5s to be left with 2 and 5 outside and 5 inside.<br>
The numbers outside multiply together same as the ones inside.<br>
We are now left with numbers with the same roots, they can be added and subtracted.<br>
10 root 5 subtract 3 root 5 is 7 root 5.<br>
Problem solved<br><br>
EDIT: Tried to make it easier to understand
 
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Basically, you have to find the smallest square root value that cannot be simplified. Think that a square root can be 'taken apart' as the multiple of other square roots. For example, we take the first one: √8 = √4 x √2. This can then be simplified as 2 x √2 or simply 2√2.<br><br>
The second set also is fairly easy: it seems that in all cases, the whole number can be split in the product of two square roots. Thus, the first one again: 2/√2 = (√2x√2)/√2 = √2.<br><br>
third set: again, just simplify the larger square root, so that the square roots are equal. The first one needs no further simplification, and √2 + 2√2 = 3√2. Others might need simplification, like number 4). Use the method above (first set) to see how.<br><br>
Fourth set: you should be getting the hang of it by now. Combine what you have done before, and it should not be too hard<br><br>
Fifth set: you can multiply the numbers under the √ with each other, and the numbers in front of it separately (if no number in front, imagine a 1). Thus, 2√2x4√12 = 8√24. Then simplify that one: 8√24 = 8x√4x√6 = 8x2x√6 = 16√6<br><br>
Good luck<br><br>
PS: FlaKing: he does not need the numerical answers; he needs to simplify them, while still leaving surds in the answer. Calculated outcomes are not surds.
 
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yo what syllabus you with niko?
 

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Gah, sorry I didn't read the part where it said you had to leave it square root form. I have no idea what surd is lol.
 

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surd is an irrational number, like a square root that cannot be further simplified <img alt="" class="inlineimg" src="/images/smilies/smile.gif" style="border:0px solid;" title="Smile">
 
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