tim gia tri lon nhat cua bieu thuc \(f\left(x\right)=\dfrac{1}{x^4-x^2+1}\)
tim gia tri lon nhat
cua bieu tthuc \(M=\dfrac{x^2}{x^4+x^2+1}\)
Cho \(xy+\sqrt{\left(1+x\right)^2\left(1+y\right)^2}=\sqrt{2017}\)
Tinh gia tri cua bieu thuc: \(P=x+\sqrt{1+y^2}+y\sqrt{1+x^2}\)
Giup mk!!!
cho a c la cac so thuc khong am thoa man dieu kien a+b+c=3 tim gia tri lon nhat cua bieu thucP=a\b3+1+b\c3+1+c\a3+1
cho x,y>0 va \(x+y\le1.\)
tim GTNN cua bieu thuc \(A=\dfrac{1}{x^2+y^2}+\dfrac{1}{xy}\)
cho a=4+\(\sqrt{5}\) va b=4-\(\sqrt{5}\) tinh gia tri cua bieu thuc
A=\(\left(a^{2019}-8a^{2018}+11a^{2017}\right)\)+\(\left(b^{2019}-8b^{2018}+11b^{2017}\right)\)
Rut gon bieu thuc sau:
\(A=\left(\dfrac{a-\sqrt{a}}{\sqrt{a}-1}-\dfrac{\sqrt{a}+1}{a+\sqrt{a}}\right):\left(\dfrac{\sqrt{a}+1}{a}\right)\)
Cho tam giac ABC; M la diem nam trong tam giac. Goi H;D;E lan luot la hinh chieu cua M tren BC;CA;AB. xac dinh vi tri M de S=BC/MH+AC/MD+AB/ME nho nhat.
1/ giai phuong trinh : \(\sqrt{\dfrac{2x+2}{x+2}}-\sqrt{\dfrac{x+2}{2x+2}}=\dfrac{7}{12}\)
2/ cho tam giac ABC vuong tai A, phan giac AD;AE.
a/ chung minh \(\dfrac{\sqrt{2}}{AD}=\dfrac{1}{AB}+\dfrac{1}{AC}\)
b/ he thuc tren thay doi nhu the nao neu BAC=60o ? BAC=120o
c/ he thuc tren thay doi nhu the nao neu thay doi phan giac trong AD voi phan giac ngoai AE
