( 4.27 + x ) : 2.4
Kêt qua CUA x trong bieu thuc la
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)
1) Cho bieu thuc: \(B=\left(\frac{\sqrt{x}}{\sqrt{x}+4}+\frac{4}{\sqrt{x}-4}\right):\frac{x+16}{\sqrt{x}+2}\left(x\ge0,x\ne16\right)\)
a) Cho bieu thuc A= \(\frac{\sqrt{x}+4}{\sqrt{x}+2}\) ; voi cac cua bieu thuc A va B da cho, hay tim cac gia tri cua x nguyen de gia tri cua bieu thuc B(A;-1) la so nguyen
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
1. cho x+y=7 va xy=8 gia tri cua bieu thuc x3+y3 = ?
2. gia tri lon nhat cua bieu thuc B= 1+3x-x2 la ?
1. cho x+y=7 va xy=8 gia tri cua bieu thuc x3+y3 = ?
2. gia tri lon nhat cua bieu thuc B= 1+3x-x2 la ?
ket qua cua bieu thuc 128 mol 3 la
128 chia 3 = 42 dư 2(128-126=2) do xài mod nên kquả = 2
Cho biểu thức A = x^2+3/x-2
a tim dieu kien cua x de gia tri cua bieu thuc khong xac dinh duoc
b. Voi nhung gia tri nao cua x thi bieu thuc A nhan gia tri la so a
cho biet x=-2 la nghiem cua da thuc p(x)=ax+b tinh gia tri bieu thuc 2011a+b/3a-b
gia tri nho nhat cua bieu thuc P=(x-1)(x+2)(x+3)(x+6) la ?
Ta có:
P = [(x-1)(x+6)] [(x+2)(x+30] = (x^2+5x-6)(x^2+5x+6)
= (x^2+5x)^2 - 6^2
= (x^2 + 5x)^2 - 36
=> Min P=-36 <=> x^2 = 5x..........( tứ diệp thảo tự tìm x nha)