3x^n(63x^n-3 + 1)-2x^n(9x^n-3-(9x^n-3 -1)
tính 3x^n*(6x^n-3+1)-2x^n* (9x^n-3 -1)
3xn(6xn-3+1)-2xn(9xn-3-1)
=xn [3(6xn-3+1)-2(9xn-3-1]
=xn (18xn-3+3-18xn-3+2)
=5xn
Chúc bn học giỏi nha!!!!
Rút gọn biểu thức
\(3x^n\left(6x^{n-3}+1\right)-2x^n\left(9x^{n-3}-1\right)\)
\(=\left(18x^{2n-3}+3x^n\right)-\left(18x^{2n-3}-2x^n\right)\)
\(=18x^{2n-3}+3x^n-18x^{2n-3}+2x^n\)
\(=\left(18x^{2n-3}-18x^{2n-3}\right)+\left(3x^n+2x^n\right)\)
\(=5x^n\)
\(=18x^{2n-3}+3x^n-18x^{2n-3}+2x^n=5x^n\)
\(3x^n\left(6x^{n-3}+1\right)-2x^n\left(9x^{n-3}-1\right)\)
\(3x^n\left(6x^{n-3}+1\right)-2x^n\left(9x^{n-3}-1\right)\)
\(=3x^n\cdot6x^{n-3}+3x^n-2x^n\cdot9x^{n-3}+2x^n\)
\(=18x^{2n-3}+3x^n-18^{2x-3}+2x^n\)
\(=3x^n+2x^n\)
\(=5x^n\)
3xn(6xn-3+1)-2xn(9xn-3-1)
\(3x^n\left(6x^{n-3}+1\right)-2x^n\left(9x^{n-3}-1\right)\)
\(=18x^{n-3}n^n+3n^n-18x^{2n-3}+2x^n\)
a. \(3x^n\left(6x^{n-3}+1\right)-2x^n\left(9x^{n-3}-1\right)\))
\(=18x^{2n-3}+3x^n-18x^{2n-3}+2x^n=5x^n\)
Rút gọn
3xn(6xn-3+1) -2xn(9xn-3-1)
\(3x^n\left(6x^{n-3}+1\right)-2x^n\left(9x^{n-3}-1\right)\)
\(=3x^n.6x^{n-3}+3x^n-2x^n.9x^{n-3}+2x^n\)
\(=18x^{-3}-18x^{-3}+5x^n=5x^n\)
Chúc bạn học tốt!!!
a)5n+1 -4.5n
b)3xn.(6xn-3+1)-2xn(9xn-3-1)
a)5n+1 -4.5n=5n.5-4.5n=5n(5-4)=5n
b)3xn.(6xn-3+1)-2xn(9xn-3-1)=18x2n-3+3xn-182n-3+2xn
=3xn+2xn=5xn
1. Thu gọn
a, 3x^n-2 . (x^n+2 -y^n+2 ) + y^n+2 . (3x^n-2 - y^n-2 )
b, 3x^n.(6x^n-3+1)-2x^n . (9x^n-3-1)
c, 5^n+1-4.5^n
d,6x^n : (x^2-1)+2x. (3x^n-1+1)
a) \(=3x^{n-2}.x^{n+2}-3x^{n-2}.y^{n+2}+y^{n+2}.3x^{n-2}-y^{n+2}.y^{n-2}\)
\(=3x^n-y^n\)
b) ; c) ; d) Tương tự nhé
thực hiện phép tính
\(3x^n\left(6x^{n-3}+1\right)-2x^n\left(9x^{n-3}-1\right)\))
\(3x^n\left(6x^{n-3}+1\right)-2x^n\left(9x^{n-3}-1\right)\)
\(=18x^{2n-3}+3x^n-18x^{2n-3}+2x^n\)
\(=3x^n+2x^n\)
\(=5x^n\)