Question

(x^-2 - y ^-2/y^-2 + y^-2/x^-2+y^-2)*(y/x)^-2

Answer 1

Ответ:

$(x^{-2} -\frac{y ^{-2}}{y^{-2}}+ \frac{y^{-2}}{x^{-2}} +y^{-2}})*(\frac{y}{x})^{-2}=(\frac{1}{x^2} -1+\frac{x^2}{y^2} +\frac{1}{y^2})*(\frac{x}{y})^2=(\frac{1}{x^2}-1+\frac{x^2+1}{y^2})*\frac{x^2}{y^2}=\frac{y^2-x^2y^2+x^2*(x^2+1)}{x^2y^2}* \frac{x^2}{y^2} =\frac{y^2-x^2y^2+x^4+x^2}{y^2} *\frac{1}{y^2}=\frac{y^2-x^2y^2+x^4+x^2}{y^4}$