Question

Если a-(1/5)=0,5 то, (a^2+(1/a^2))^0.5 =?

Answer 1

$a-\frac{1}{a}=0,5\\\\(a-\frac{1}{a}){2}=0,5^{2} \\\\a^{2} -2*a*\frac{1}{a} +\frac{1}{a^{2}} =0,25\\\\a^{2}-2+\frac{1}{a^{2}}=0,25\\\\a^{2}+\frac{1}{a^{2}}=2,25\\\\\\(a^{2}+\frac{1}{a^{2}} )^{0,5} =2,25^{0,5}\\\\(a^{2}+\frac{1}{a^{2}})^{0,5}=\sqrt{2,25}\\\\(a^{2}+\frac{1}{a^{2}} )^{0,5}=1,5$