[tex](2- \frac{3}{2})^ {-5} : (- \frac{25}{100} )^8 * (-\frac{1}{2})^ {101} = \\ (\frac{1}{2}) ^ {-5} : (-\frac{1}{4})^8 * (-\frac{1}{2})^ {101} = \\ (\frac{1}{2}) ^ {-5} : (\frac{1}{2})^{16} * (-\frac{1}{2})^ {101}=\\(\frac{1}{2}) ^ {-5-16} * (-\frac{1}{2})^ {101}= \\ (\frac{1}{2}) ^ {-21} * (-\frac{1}{2})^ {101} =\\ - ( \frac{1}{2})^{-21+101} = \\ - ( \frac{1}{2})^{80}[/tex]
b) a= 25/100 * b
(a+b)/2 =37,5 => a+b = 37,5*2= 75
a+b=75 = > a= 75-b (inlocuim in prima relatie si obtinem:)
75-b = 25/100 * b
75-b = b/4
75= b/4+b
75= 5b/4
5b= 300
b= 300:5
b=60
a= 75-60
a=15
[tex]\sqrt{63} +2(\sqrt{14}:\sqrt{2} +5 ) -\sqrt{175} = \\ \sqrt{63} +2(\sqrt{7} +5 ) -\sqrt{175} =\\ \sqrt{63} +2 \sqrt{7}+10 -\sqrt{175} = \\ 3\sqrt{7}+2 \sqrt{7}+10 - 5 \sqrt{7} = \\ 5 \sqrt{7} +10 -5 \sqrt{7} = \\ 10[/tex]
deci apartine lui N ( multimea nr naturale)
