x=1/2

ta có x=1 , thế vào f(x)

x=0 và y=0

1+6+15+20+15+6+1=64

P=\(\dfrac{4x-4\sqrt{4x-1}+8060}{4}\)

P=\(\dfrac{\left(\sqrt{4x-1}\right)^2-2\sqrt{4x-1}.2+2^2+8056}{4}\)

P=\(\dfrac{\left(\sqrt{4x-1}-2\right)^2}{4}+2014>=2014\)

dấu"=" xảy ra \(\Leftrightarrow\sqrt{4x-1}-2=0\)

\(\Leftrightarrow\sqrt{4x-1}=2\)

\(\Leftrightarrow4x-1=16\left(Đkm>=\dfrac{1}{4}\right)\)

\(m=\dfrac{17}{4}\)

vậy Pmax=2014 khi m=\(\dfrac{17}{4}\)

B

P=\(\left(5x-1-5x-4\right)^2\)

P=25

Q=\(\left(x-y\right)^3+x^3+3x^2y+3xy^2-\left(x-y\right)^3-3x^2y-3xy^2\)

Q=\(x^3+y^3\)

Choose the letter A, B, C or D to indicate the word whose underlined part is pronounced differently from that of the rest in each of the following questions.

A. exhaust

B. exam

C. exact

D. excellent