P= 7x²-3xy³+4
P= 7.(-2)²-3.(-2).(-1/2)³+4
=7.4-3.(-2).(-1/8)+4
=28-(-6).(-1/8)+4
=28-3/4+4
=109/4+4
=125/4
kb đúng hay sai.

Có: 7-3.\(\frac{-1}{4}^2\)

= 7-3. \(\frac{1}{16}\)

= 7- \(\frac{3}{16}\)

= \(\frac{112}{16}\)-\(\frac{3}{16}\)

= \(\frac{109}{16}\)

Đề bài yêu cầu j vậy?

mũ 2 tui ko bt

co ai giai dc ko cau 60 % .....

$\textbf{Ta có:}$

$A=\dfrac{-5^2-5\cdot3^2}{5^3+5^2\cdot3^2}$

$=\dfrac{-25-45}{125+225}$

$=\dfrac{-70}{350}$

$=-\dfrac15.$

Và

$B=\dfrac{2^{12}\cdot3^{10}+6^9\cdot120}{2^{12}\cdot3^{12}-2^{11}\cdot3^{11}}$

$=\dfrac{2^{12}3^{10}+2^{12}3^{10}\cdot5}{2^{11}3^{11}(2\cdot3-1)}$

$=\dfrac{2^{12}3^{10}(1+5)}{2^{11}3^{11}\cdot5}$

$=\dfrac{2^{12}3^{10}\cdot6}{2^{11}3^{11}\cdot5}$

$=\dfrac{2^2}{5}$

$=\dfrac45.$

=> $M=B-A$$=\dfrac45-\left(-\dfrac15\right)$

$=\dfrac55$$=1.$

dài vãi

Ta có: \(\frac{-1}{9}\cdot\frac{-3}{5}-\frac56\cdot\frac{3}{-5}+\frac{-5}{2}\cdot\frac35\)

\(=\frac19\cdot\frac35+\frac56\cdot\frac35+\frac35\cdot\frac{-5}{2}\)

\(=\frac35\left(\frac19+\frac56-\frac52\right)\)

\(=\frac35\left(\frac{2}{18}+\frac{15}{18}-\frac{45}{18}\right)=\frac35\cdot\frac{2-30}{18}=\frac35\cdot\frac{-28}{18}=\frac35\cdot\frac{-14}{9}=\frac{-42}{45}=-\frac{14}{15}\)

bằng 19/44 nhá

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