Thu gọn :
a) \(2^{n-1}+2.2^{n+3}-8.2^{n-4}-16.2^n\)
b) \(\left(3^{n+1}-2.2^n\right)\left(3^{n+1}+2.2^n\right)-3^{2n+2}+\left(8.2^{n-2}\right)\)
Thu gọn A=2n-1+2.2n+3-8.2n-4-16.2n
Rút gọn phân thức \(M=2^{n-1}+2.2^{n-3}-8.2^{n-4}-16.2^n\)
Ai giup m voi: Thu gon roi tinh bieu thuc sau:
C= x^5 - 5x^4 + 5x^3 - 5x^2 + 5x -1 voi x=4
giai chi tiet giup to may bai nay nha
1. Cho tam giac ABC co trung tuyen AM . Goi I la trung diem cua AM. Tia BI cat AC tai D, qua M ke duong song song voi BD cat CD tai E. Biet BD=18cm , khih do ID = ? cm
2. gia tri lon nhat cua bieu thuc Q= 5-x2+2x2-4y2-4y
3 . gia tri cua x thoa man (12x-5)(4x-1)+(3x-7)(1-16x)=81 , x=?
4. x+y=3 , gia tri cua bieu thuc Q = x2+2xy+y2-4x-4y+1=?
5 . a+b+c=0 va abc=-2 thi a3+b3+c3= ?
6. rut gon bieu thuc(a2+b2)2-4a2b2voi a2-b2=5 ta duoc ket qua ?
giup mink nhe !!
rut gon bieu thuc sau
(2x-y+5)^2+(4x-2y+10)(y-2x)+(2x-y)^2
CMR:
a,Bieu thuc : n(2n-3)-2n(n+1) luon chia het cho 5 voi moi n la so nguyen
b,Bieu thuc (n-1 )(n+4) - (n-4) (n+1)
Rut gon bieu thuc:
A=\(8x^{n-1}.\left(\frac{1}{2}x^{n+1}-\frac{3}{4}x\right)\)
thu gọn
A= (2n-1+2.2n).(3n+1+2.2n)-32n+2+(8.2n-2)2