Tinh gia tri bieu thuc [m + n ]:p neu m=5,n=19 va p=3 .Vay gia tri bieu thuc la:
gia tri cua bieu thuc ; m+4050⋮5 voi m=2945 la ............... gia tri cua bieu thuc;n-57*13 voin=9876 la...................
\(m+4050=2945+4050=6995\)
\(n-57\times13=9876-57\times13=9876-741=9135\)
bai 1 tinh gia tri cua bieu thuc 78 x m + 22 x m voi m =135
bai 2 tinh gia tri cua bieu thuc 78 x m + 42 x m -20 x m voi m =1035
bai 3 cho bieu thuc B = 119 x n - n x 9 bieu thuc B co gia tri bang 8470 khi n =............
bai 1 dien vao cho ....
a)1 bieu thuc co 1 phap tinh cong va 1phep tinh tru co gia tri la 50 ....
b)1 bieu thuc co 1phep tinh chia va 1 phep tinh nhan co gia tri la 24......
bai 1
cho bieu thuc A = 5/n+1 voi N THUOC Z
a, de A la phan so thi n co dieu kien gi ?
b , tim tat ca cac gia tri nguyen cua n de gia tri A la 1 so nguyen ?
bai 2
cho bieu thuc M = 6/n-3 voi n thuoc Z .Co bao nhieu gia tri cua n de :
a, M ko phai la phan so
b , M la phan so va cp gia tri nguyen ?
bai 3 viet tap hop cacs so nguyen sao cho :
-12/4 < x <6/3
Bài 1:
a: Để A là phân số thì n+1<>0
hay n<>-1
b: Để A là số nguyên thì \(n+1\in\left\{1;-1;5;-5\right\}\)
hay \(n\in\left\{0;-2;4;-6\right\}\)
Cho bieu thuc m x 3 + n x 4 + p x 2 + m + 2 x p . Voi m + n + p = 2009 thi gia tri cua bieu thuc la :
=m x 3 + m + n x 4 + p x 2 + p x 2
=m x 3 + m x 1 + n x 4 + p x 2 + p x 2
=m x (3 + 1) + n x 4 + p x (2 + 2)
=m x 4 + n x 4 + p x 4
=(m + n + p) x 4
=2009 x 4
=8036
=m + n + p)
CHO bieu thuc
B=17,58*43+57*17,58/293*A
a)tim gia tri cua bieu thuc Bkhi a=2
b)tinh gia tri a khi B=2
c)tim gia tri so tu nhien ad biet bieu thuc B co gia tri lon nhat ,gia tri lon do la bao nhieu
Thu gon bieu thuc sau roi tim gia tri cua x de bieu thuc co gia tri la so am
7 × -19 × x + 6 × x
TINH GIA TRI BIEU THUC
3 * M + 5 * N + 2 * M + N + M VOI M+ N = 25
3 x M + 5 x N + 2 x M + N + M
= M x ( 2 + 3 ) + 5 x N + ( M + N )
= 5 x M + 5 x N + ( M + N )
= 5 x ( M + N ) + ( M + N )
= ( M + N ) x ( 5 + 1 )
= ( M + N ) x 6
= 25 x 6
= 150
Cho x+y=2, tinh gia tri cua bieu thuc:
M=3(x^2+y^2)-(x^3+y^3)+1
Bai 2:Cho a+b=5,tinh gia tri bieu thuc:
M=3a^2-2a+3b^2-2b+6ab+100