Question

Thực hiện phép tính

a) 3x\(^n\)(6x\(^{n-3}\)+1) - 2x\(^n\)(9x\(^{n-3}\)-1)

b) 5\(^{n+1}\)- 4.5\(^n\)

Answer 1

a. \(3x^n\left(6x^{n-3}+1\right)-2x^n\left(9x^{n-3}-1\right)=18x^{2n-3}+3x^n-18x^{2n-3}+2x^n=5x^n\)

b. \(5^{n+1}-4.5^n=5^n.5-4.5^n=5^n\left(5-4\right)=5^n\)

Answer 2

a,\(3x^n\left(6x^{n-3}+1\right)-2x^n\left(9x^{n-3}-1\right)\)

=\(18x^{2n-3}+3x^n-18x^{2n-3}+2x^n\)

=\(5x^n\)

b,\(5^{n+1}-4.5^n\)

\(=5^n.5-4.5^n\)

\(=5^n\)