I need help with factorising the following: a) (c+d)^2 - d^2 I got c^2 + 2cd + d^2 - d^2 which is equal to c^2 + 2cd, is this correct please? b) 2w^2 + w - 3 How do you do this again please (need simple and clear advice)? Thanks
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Originally Posted by Natasha1 I need help with factorising the following: a) (c+d)^2 - d^2 I got c^2 + 2cd + d^2 - d^2 which is equal to c^2 + 2cd, is this correct please? b) 2w^2 + w - 3 How do you do this again please (need simple and clear advice)? Thanks For the first one I think they wanted you to use the difference of squares. so in your case For b notice that and now factor by grouping. Notice to break up the middle term we found factors of that add up to the middle term
Originally Posted by Natasha1 I need help with factorising the following: a) (c+d)^2 - d^2 I got c^2 + 2cd + d^2 - d^2 which is equal to c^2 + 2cd, is this correct please? It's almost complete, notice that "c" is common... c(c+2d) is fully factored. Also, the method shown by TheEmptySet is very useful. b) 2w^2 + w - 3 How do you do this again please (need simple and clear advice)? Thanks Examine "a" and "b" to find out how we get a single "w" after multiplying out the factors.... Since "b" will be multiplied by 2, we see that it needs to be
here is how i did the first equation. is a positive perfect square. expand perfect square. collect d squared terms they cancel. factor out c.
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