borgyX Posted October 13, 2005 Share Posted October 13, 2005 i remember my algebra 2...once lang ako natulog sa class buong college..sa algebra 2 pa...huli ni prof...tinawag tuloy ako sa board to answer a problem na wala ako idea Quote Link to comment
keymaker Posted October 15, 2005 Share Posted October 15, 2005 Karamihan ng knowledge ko about math nakalimutan na. Quote Link to comment
ninj@ Posted October 21, 2005 Share Posted October 21, 2005 There are three kinds of mathematicians: those who can count and those who can't. Quote Link to comment
b_junzo Posted October 27, 2005 Share Posted October 27, 2005 There are three kinds of mathematicians: those who can count and those who can'tninj@ kala ko three kinds bat dalawa lang ata? Quote Link to comment
Guest wackeen Posted October 27, 2005 Share Posted October 27, 2005 There are three kinds of mathematicians: those who can count and those who can'tninj@ kala ko three kinds bat dalawa lang ata?<{POST_SNAPBACK}> and of course, you're kidding when you ask that right? tatlo nga: kami ni ninja dalawa -- hulaan mo kung sino yung isa pa? peace, brother! Quote Link to comment
dem0liti0nman Posted November 9, 2005 Share Posted November 9, 2005 Solid Geometry take 2! Engineering Mechanics take 2! Quote Link to comment
dem0liti0nman Posted November 9, 2005 Share Posted November 9, 2005 There are three kinds of mathematicians: those who can count and those who can'tninj@ kala ko three kinds bat dalawa lang ata?<{POST_SNAPBACK}> and of course, you're kidding when you ask that right? tatlo nga: kami ni ninja dalawa -- hulaan mo kung sino yung isa pa? peace, brother! <{POST_SNAPBACK}> b_junzo, wag kang mag-alala hindi kaw ung pangatlo peace man! Quote Link to comment
Moonwalker Posted November 10, 2005 Share Posted November 10, 2005 Beatrice spent all of her money in five stores. In each store, she spent 1 peso more than half of what she had when she came in. How much money did Beatrice have when she entered the first store? Quote Link to comment
redshift Posted November 10, 2005 Share Posted November 10, 2005 Beatrice spent all of her money in five stores. In each store, she spent 1 peso more than half of what she had when she came in. How much money did Beatrice have when she entered the first store?<{POST_SNAPBACK}> P62.00? Quote Link to comment
floppydrive Posted November 12, 2005 Share Posted November 12, 2005 62 din kwenta ko para wala na siyang pera paglabas ng huling tindahan. Quote Link to comment
Moonwalker Posted November 12, 2005 Share Posted November 12, 2005 tumpak po 62 pesos may solution po ba kayo? Quote Link to comment
mick8 Posted November 15, 2005 Share Posted November 15, 2005 can anyone give me a simpler explanations about Euler's identity? the explanation that can be found over the net are very complex. thanks. Quote Link to comment
Guest wackeen Posted November 15, 2005 Share Posted November 15, 2005 can anyone give me a simpler explanations about Euler's identity? the explanation that can be found over the net are very complex. thanks.<{POST_SNAPBACK}> There's an extension of the real number system called the complex numbers. The numbers in this larger system can be expressed in a number of ways: 1) a+bI2) r cis t In handling the more powerful second type of notation, there are 'rules' to follow. But note that this is not just shorthand, but has an actual meaning. The Euler identity is the foundation for such a notation to be possible. Quote Link to comment
mick8 Posted November 15, 2005 Share Posted November 15, 2005 There's an extension of the real number system called the complex numbers. The numbers in this larger system can be expressed in a number of ways: 1) a+bI2) r cis t In handling the more powerful second type of notation, there are 'rules' to follow. But note that this is not just shorthand, but has an actual meaning. The Euler identity is the foundation for such a notation to be possible.<{POST_SNAPBACK}> bro, what do you mean by, "an extension of the real number system"? & can you give an example if possible, thanks. Quote Link to comment
PageDown Posted November 15, 2005 Share Posted November 15, 2005 246 I don't know enough of number theory, so this is what I used instead to get the answer (it's real clunky, so apologies ): The largest sum possible for two 3-digit numbers is 1998, so _IF_ the sum of the mystery number and 596 results in a 4 digit number then this 4 digits would look like either of these two (since they are in geo. progression): b b*r b*r^2 b*r^3b*r^3 b*r^2 b*r b (where each digit <=9) With the leftmost digit (either 'b' or 'b*r^3') being a 1 (since we're checking the case where the sum is a 4 digit number). So now we have either of these two conditions (since the leftmost digit is a 1): b=1b*r^3=1 In the first case, if b=1 then r=1 or 2 (since in this case, the rightmost digit 'b*r^3' must be <=9, thus r can at most only be equal to 2). Thus the possible 4-digit numbers here would be 1111 (b=1,r=1) and 1248 (b=1,r=2). Subtracting 596 from these yields 515 and 652, niether of which are in arith. progress. So this case is false. If we take the second case, b*r^3=1, then b=r=1. Which again yields the possible 4-digit number 1111, subtracting 596 gives 515 which again isn't in arith. progress. so this case is false as well. So the above shows that the sum of the mystery number and 596 cannot be a 4-digit number. Ok, so now we know the sum is a 3-digit number, hence in the following form: b b*r b*r^2b*r^2 b*r b We also know each digit <=9 and since 596 is being added the leftmost digit must >=6, thus: 9 >= b >= 69 >= b*r^2 >= 6 Taking the second case, b*r^2, there are only 3 possible values allowed for r (due to the <=9 condition for each digit), hence drawing a matrix for values of b given the allowed values for r: b*r^2 b (r=1) b (r=2) b (r=3)------- -------- --------- --------- 6 6 X X 7 7 X X 8 8 2 X 9 9 X 1 ('X' marks non-valid combinations) Which gives 6 possible 3-digit numbers for the sum of the mystery number and 596: 666 (b=6,r=1)777 (b=7,r=1)888 (b=8,r=1)999 (b=9,r=1)842 (b=2,r=2)931 (b=1,r=3) Subtracting 596 from each will show that only 842 will give you a 3-digit number (i.e. 246) which has it's digits in arith. progress. Now for the first case, 9>=b>=6 ... nah, I'm too lazy, besides I've already got at least one answer <{POST_SNAPBACK}> Nope! you have to use a 4 x 4 matrix to get to it (easier solution). Quote Link to comment
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