mono_poly.md

@@ -260,7 +260,7 @@ Réduire et ordonner les expressions algébriques ci-dessous.
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 3. $\quad \left(\dfrac{2ab^2}{3}\right)^3 \cdot \dfrac{9a^2}{4b^3} \cdot \dfrac{2b}{a^2} = \dfrac{8a^3b^6}{27} \cdot \dfrac{9a^2}{4b^3} \cdot \dfrac{2b}{a^2} = \dfrac{8 \cdot 9 \cdot 2 \cdot a^{3+2-2} \cdot b^{6-3+1}}{27 \cdot 4} = \dfrac{144a^3b^4}{108} = \boxed{\dfrac{4a^3b^4}{3}}$
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-4. $\quad \dfrac{4x^3y^2z}{3xy} \cdot \dfrac{6xyz^2}{8x^2z} \cdot \dfrac{9x^2y}{2yz^2} = \dfrac{4 \cdot 6 \cdot 9 \cdot x^{3+1+2} \cdot y^{2+1+1} \cdot z^{1+2-2}}{3 \cdot 8 \cdot 2 \cdot x^{1+2} \cdot y^{1+1} \cdot z^{1+2}} = \dfrac{216x^6y^4z}{48x^3y^2z^3} = \dfrac{216x^3y^2}{48z^2} = \boxed{\dfrac{9x^3y^2}{2z^2}}$
+4. $\quad \dfrac{4x^3y^2z}{3xy} \cdot \dfrac{6xyz^2}{8x^2z} \cdot \dfrac{9x^2y}{2yz^2} = \dfrac{4 \cdot 6 \cdot 9 \cdot x^{3+1+2} \cdot y^{2+1+1} \cdot z^{1+2}}{3 \cdot 8 \cdot 2 \cdot x^{1+2} \cdot y^{1+1} \cdot z^{1+2}} = \dfrac{216x^6y^4z^3}{48x^3y^2z^3} = \dfrac{216x^3y^2}{48} = \boxed{\dfrac{9x^3y^2}{2}}$
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 5. $\quad 2x^3y - 3x^2y^2 + xy^3 - x^3y + 2x^2y^2 - 3xy^3 + 5x^3y - xy^3$
    $= (2-1+5)x^3y + (-3+2)x^2y^2 + (1-3-1)xy^3 = \boxed{6x^3y - x^2y^2 - 3xy^3}$