Can you check my answer and the work? Thank youu~~

Question

(2x-y)7

128x7 -448x6y -672x5y2 -560x4y3 -280x3y4 -84x2y5 -14xy6 -y7

orr

128x7 -448x6y +672x5y2 - 560x4y3 +280x3y4 -84x2y5 +14xy6 -y7

Ps: the 7 in the equation is the exponent and the numbers after the variable are also the exponent

Answer 1

+ 672x^5y^2 - 280x^3y^4 + 14xy^6

only the signs were wrong for the above
corrections

I used an online calculator to expand so I know it's right

Answer 2

so is it this?
128x7 -448x6y +672x5y2 - 560x4y3 +280x3y4 -84x2y5 +14xy6 -y7

or

128x7 -448x6y +672x5y2 -280x3y4 +14xy6

?

Answer 3

sorry, I didn't see your 2nd line after
"or", so the correction applies to your first line/answer

Answer 4

k thank youuu~~~ =)

Answer 5

you're welcome