Question

[Sffhould]

tìm giá trị lớn nhất

A = 5 - |2/3 - x|

B = 7 - |4x - 3|

Answer 1

[o0o Mạc Thiên Lạc o0o]

\(\text{Ta có: }\)\(\left|\frac{2}{3}-x\right|\ge0\)\(\text{dấu "=" xảy ra khi }\)\(\frac{2}{3}-x=0\Leftrightarrow x=\frac{2}{3}\)

\(\text{Vậy:}\) \(A_{Max}=5\Leftrightarrow x=\frac{2}{3}\)

\(\text{ Ta có:}\)\(\left|4x-3\right|\ge0\)\(\text{dấu "=" xảy ra khi}\)\(4x-3=0\Leftrightarrow x=\frac{3}{4}\)

\(\text{Vậy:}\)\(B_{Max}=7\Leftrightarrow x=\frac{3}{4}\)