3.) The product of 3 less than twice x and 2 more than the quantity 3 times x...we can think of this as:
Product of (2x - 3) and (3x + 2)...3 less than twice x is the same as twice x - 3 or 2x - 3 & 2 more than the quantity 3 times x is the same as 3 times x plus 2 = 3x + 2 -->
(2x - 3)*(3x + 2)
Now, FOIL: first, outside, inside, & last -->
first: 6x^2
outside: 4x
inside: -9x
last: -6
Add all the terms: 6x^2 + 4x - 9x - 6...lastly, simplify by collecting "like" terms -->
D, 6x^2 - 5x - 6.
4.) [(5x(x+1)^2) / (x^3(x^3 + 9x))] * [(x^2 + 9) / (x + 1)]
Notice, we can get rid of the (x+1)'s leaving us with:
5x(x+1) / x^3(x^3 + 9x) * [(x^2 + 9)]
5x(x+1) / x^3*x(x^2 + 9) * [(x^2 + 9)]
5x(x+1) / x^4(x^2 + 9) * [(x^2 + 9)]
5x(x+1) / x^4
Get rid of the x in 5x by taking away 1 x from x^4:
C, 5(x+1) / x^3.
3.) The product of 3 less than twice x and 2 more than the quantity 3 times x...we can think of this as:
Product of (2x - 3) and (3x + 2)...3 less than twice x is the same as twice x - 3 or 2x - 3 & 2 more than the quantity 3 times x is the same as 3 times x plus 2 = 3x + 2 -->
(2x - 3)*(3x + 2)
Now, FOIL: first, outside, inside, & last -->
first: 6x^2
outside: 4x
inside: -9x
last: -6
Add all the terms: 6x^2 + 4x - 9x - 6...lastly, simplify by collecting "like" terms -->
D, 6x^2 - 5x - 6.
4.) [(5x(x+1)^2) / (x^3(x^3 + 9x))] * [(x^2 + 9) / (x + 1)]
Notice, we can get rid of the (x+1)'s leaving us with:
5x(x+1) / x^3(x^3 + 9x) * [(x^2 + 9)]
5x(x+1) / x^3*x(x^2 + 9) * [(x^2 + 9)]
5x(x+1) / x^4(x^2 + 9) * [(x^2 + 9)]
5x(x+1) / x^4
Get rid of the x in 5x by taking away 1 x from x^4:
C, 5(x+1) / x^3.
My answer is the same as Ninja's and Ninja is very good at explaining things but maybe a different presentation will help.
3 less than twice x is (2x-3) I just put it in brackets to make it clear
and
2 more than the quatity 3 times x is (3x+2)
and product means multiply
so the product of these is
(2x-3)*(3x+2) = (2x-3)(3x+2)
and when you expand that out you get
$$(2x-3)(3x+2)\\
=2x(3x+2)-3(3x+2)\\
=6x^2+4x-9x-6\\
=6x^2-5x-6$$
Is that any clearer?? If not let us know and we will explain some more.
Now my problem is to understand the expressions 3 less than twice x You know that English is not my mother language =D .. What is less than mean !
Look at it this way.....if I gave you "2 less than 5"...isn't that just 5 - 2??
Then, "twice x " is just 2x
And three less than "twice x" is just....... 2x - 3
Does that make sense??
Thanks Chris , sorry 15x3 there has been a lot of questions and I only just got back to yours.