Question

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Answer 1

well using the formula for binomial expansion its

\[^5C_{r} (2x)^{5 - r} \times (3)^r\]

to get x^3 the value of r is 2

so substitute r = 2 and evaluate....

hope it helps

Answer 2

i still don't quite understand

Answer 3

ok...

so the the combination..

\[^5C_{2} = \left(\begin{matrix}5 \\ 2\end{matrix}\right)\]

then you need to multiply it by

\[(2x)^3\]

then lastly you need to multiply by

\[3^2\]

does that help

Answer 4

5C2 = 10
10*(2x)^3 = (20x)^3
(20x)^3 (9) = (180x)3
im not sure if this is correct

Answer 5

nope...

(2x)^3 = 8x^3

(3)^2 = 9

so its

10 * 8x^3 * 8

= 720x^3

so the coefficient is 720

Answer 6

thanks