Question

(2х^2+5y^3)(5y^3-2x^2) при х^4=1/4, у^2=2

Answer 1

Ответ:

$199$

Объяснение:

$(2x^{2}+5y^{3})(5y^{3}-2x^{2})=(5y^{3}+2x^{2})(5y^{3}-2x^{2})=(5y^{3})^{2}-(2x^{2})^{2}=5^{2} \cdot (y^{3})^{2}-$

$-2^{2} \cdot (x^{2})^{2}=25 \cdot y^{3 \cdot 2}-4 \cdot x^{2 \cdot 2}=25 \cdot y^{2 \cdot 3}-4 \cdot x^{4}=25 \cdot (y^{2})^{3}-4 \cdot x^{4};$

$x^{4}=\dfrac{1}{4}, \quad y^{2}=2: \quad 25 \cdot 2^{3}-4 \cdot \dfrac{1}{4}=25 \cdot 8-1=200-1=199;$