tag:blogger.com,1999:blog-7195787896650777325.post3210655643446135912..comments2023-05-28T17:16:30.446+08:00Comments on 2011 S1-06 Maths Blog: Level Test (review) part 2Loh Kwai Yinhttp://www.blogger.com/profile/09629206529240771085noreply@blogger.comBlogger9125tag:blogger.com,1999:blog-7195787896650777325.post-54062172765218260682011-08-09T18:26:26.743+08:002011-08-09T18:26:26.743+08:00A) <5m+n> The 5 must be also multiplied with...A) <5m+n> The 5 must be also multiplied with the n resulting in 5n.<br /> the -n in 4m-n /m+n after it is in one fraction must become +n since - x - = +<br /><br />B) the m cannot be canceled out since one of them is addition .Cancelation only occurs when both are in multiplication.<br /><br />C) the result is not 7x -3. the 7 is also multiplied by -3 resulting in -21<br /> and -(20-7x) will result in -+20--70x which will result in = -20+70x<br /> <br />D) < 3(2a+1)^2 > the square belongs to the values in the brackets not including the 3 in multiplication.thus the process of squaring must occur before multiplying with 3.<br /><br />E) the expression to the right should result in +6xy -9y^2 not +6xy-9xy. <br /><><br />for (E)<br /><br />I think it is a (-3y) the whole squared since the brackets will be redundant if they are not in multiplication or other similar processes. <br />So the correct answer (-3y)^2 will result in (9)(y^2)Siddharthhttps://www.blogger.com/profile/01805326435932940797noreply@blogger.comtag:blogger.com,1999:blog-7195787896650777325.post-55569649962571575172011-08-04T19:16:10.672+08:002011-08-04T19:16:10.672+08:00A) The sign is wrong it should be 4m+n not 4m-n.
B...A) The sign is wrong it should be 4m+n not 4m-n.<br />B)You cannot cancel addition but can cancel when it is multiplication or division.<br />C)The sign convention is wrong as (-) X (-) = (+) so it should be 7x-3-20+7x<br />D)The sign convention is again wrong. When there is a negative outside the bracket always remember there is a 1 there thus you have to take note of the sign convention and thus its should be (6a-3)^2<br />E) It should be 9y^2 and -3y is also not 9y^2Ian Harijantohttps://www.blogger.com/profile/14226016232595154134noreply@blogger.comtag:blogger.com,1999:blog-7195787896650777325.post-198615864498543082011-08-03T21:53:12.799+08:002011-08-03T21:53:12.799+08:001. It should be 4m+n because if you have 3-(2-1), ...1. It should be 4m+n because if you have 3-(2-1), that would be 3-2+1.<br />2. You can not cancel in addition<br />3. 7(x-3) = 7x - 21 not 7x - 3 and then conversion error. It should be20 + 7x<br />4. Power sign comes first<br />5. -3y isn't 9x^2. Y is not XCharlene Tanhttps://www.blogger.com/profile/17305598965696495989noreply@blogger.comtag:blogger.com,1999:blog-7195787896650777325.post-81789022028952911622011-08-03T20:51:52.789+08:002011-08-03T20:51:52.789+08:001.should be 4m+n, not 4m-n
2.cancelling cannot be ...1.should be 4m+n, not 4m-n<br />2.cancelling cannot be used in addition in the denominator and numerator of the fraction<br />3.7 must be positive, not negative<br />4.power sign must be taken out first<br />5.-3y is not 9x^2Keminghttps://www.blogger.com/profile/06018168472891311477noreply@blogger.comtag:blogger.com,1999:blog-7195787896650777325.post-6385355446999875972011-08-03T20:43:39.073+08:002011-08-03T20:43:39.073+08:00A) There is error with the sign, negative times ne...A) There is error with the sign, negative times negative equals positive. So it should be 4m+n. Another problem is that, the n should have been multiplied by 5<br /><br />B) the m cannot be canceled out just like that, it must be a cross multiplication<br /><br />C) -(20-7x).. before the bracket, there is a 'invisible 1' and when it is multiplied by 1, the signs need to change too because negative times negative equals positive. so it should be, -20+7x<br /><br />D) The power sign should be done first before multiplying the numbers in the bracket, and the signs are wrong, (-)(+) = (-), it should be -36^2-9<br /><br />E) it is -(-3y), how can it become 9x^2? Numbers in the question cannot be changed.Patrickhttps://www.blogger.com/profile/09260079535769711464noreply@blogger.comtag:blogger.com,1999:blog-7195787896650777325.post-8196063078970438802011-08-03T18:28:40.832+08:002011-08-03T18:28:40.832+08:00A) Error with the sign conversion (-)(-) = (+). (-...A) Error with the sign conversion (-)(-) = (+). (-)(4m-n/m+n) should be 4 m+n.<br /><br />B) Error in division .Just like using numbers, addition and subtraction can't use this method of canceling. It should eb just 2n+m/m+n.<br /><br />C) Error in sign conversion. Just like A) (-)(-)=(+) which in this case is (-)(20-7x) which is -20+7x.<br /><br />D) Error in power sign. The power sign should be taken out first before removing the brackets. It should be in this order -3(2a+1) = -3(4a^2+1)=-12a^2-1<br /><br />E) Error in multiplication. I should be y(6x-9y) = 6xy-9y^2 not 9xy.Kevinhttps://www.blogger.com/profile/13829546390838449630noreply@blogger.comtag:blogger.com,1999:blog-7195787896650777325.post-2912325462091057172011-08-03T13:58:52.542+08:002011-08-03T13:58:52.542+08:001. The sign is wrong , -x - = + and they did not...1. The sign is wrong , -x - = + and they did not multiply the n by 5 .<br />2.They can not just cancel out the n .<br />3. The 7 was not multiplied by the 3 and the 7x is positive not negative<br />4. The ^2 needs to be done first by using the identity then multiplying by the number outside the brackets<br />5.The expansion for the y outside the bracket is wrong and the expansion for the sign is wrong and the number is wrong ( -3y)MasonSim098https://www.blogger.com/profile/17904268656623339232noreply@blogger.comtag:blogger.com,1999:blog-7195787896650777325.post-8463381960909288492011-08-03T13:27:01.701+08:002011-08-03T13:27:01.701+08:00A.The n at the numerator is to be multiplied by 5....A.The n at the numerator is to be multiplied by 5.<br />B.The m at the numerator cannot be cancelled with the m at the denominator cannot be canceled at the last part.<br />C.When removing the bracket,the -7 should become +7.<br />D.It should be -(36a^2+9) then -36a^2-9<br />E.It should be 9y^2 not 9xy and -3y should not be worked to -9x squaretaeyangahbendicthttps://www.blogger.com/profile/10074957456636572236noreply@blogger.comtag:blogger.com,1999:blog-7195787896650777325.post-26840252930401785542011-08-02T22:26:41.523+08:002011-08-02T22:26:41.523+08:001.The n should have been multiplied by 5.
2.The n ...1.The n should have been multiplied by 5.<br />2.The n should not be canceling out each other.<br />3.The 7 should not negative but positive.<br />4.(6a+3) when squared is not 36a squared+9.<br />5.-3y cannot be changed to -9x squareseanlohtwhttps://www.blogger.com/profile/07963886426680586180noreply@blogger.com