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1. write down three values of x that satisfy the equation x(x-3)(2x+1)=0

how do I do this?
write down three values of x that satisfy the equation x(x-3)(2x+1)=0

how do I do this?
For the equation to equal zero, one of the three terms in the product must equal 0.
3. (Original post by joostan)
For the equation to equal zero, one of the three terms in the product must equal 0.
so x= 0, 3, -1/2?
write down three values of x that satisfy the equation x(x-3)(2x+1)=0

how do I do this?
If

then either the first, or the second, or the third..... or the nth term is zero.
so x= 0, 3, -1/2?
yes
6. (Original post by Indeterminate)
If

then either the first, or the second, or the third..... or the nth term is zero.
OKay I got the values of x but how do I do the next bit,.? it says: hence solve the inequality x(x-3)(2x+1) > 0
7. (Original post by joostan)
yes
OKay I got the values of x but how do I do the next bit,.? it says: hence solve the inequality x(x-3)(2x+1) > 0
8. (Original post by joostan)
yes
OKay I got the values of x but how do I do the next bit,.? it says: hence solve the inequality x(x-3)(2x+1) > 0
OKay I got the values of x but how do I do the next bit,.? it says: hence solve the inequality x(x-3)(2x+1) > 0
For what values is the function greater than 0?
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10. (Original post by Felix Felicis)
For what values is the function greater than 0?
x>3, x>-0.5 x<0
x>3, x>-0.5 x<0
yes
12. (Original post by Felix Felicis)
yes
how are you meant to do this?

find a set of values of x for which both 6x-7<2x+3 and 2x^2-11x +5 >0
how are you meant to do this?

find a set of values of x for which both 6x-7<2x+3 and 2x^2-11x +5 >0
remember for this kind of question always draw an inequality line.

Work out x values for both equations first, then draw the inequality line for both equations and then you should see values of x which satisfiy both equations. (hope that makes sense)
14. Solve both inequalities and adjust the set of solutions accordingly
15. (Original post by gaffer dean)
remember for this kind of question always draw an inequality line.

Work out x values for both equations first, then draw the inequality line for both equations and then you should see values of x which satisfiy both equations. (hope that makes sense)
Thanks lad! One thing.. What's an equality line?
Thanks lad! One thing.. What's an equality line?
see this: http://www.sparknotes.com/math/algeb...section4.rhtml

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