Odpowiedź:
[tex]a) \\x^{4} -81=0\\x^{4} =81\\\\x^{2} =9, x = 3 \\lub\\x^{2} =-9, x=-3[/tex]
[tex]b) \\16x^{4} -1=0\\16x^{4} =1\\x^{4}=\frac{1}{16} \\x^{2} =\frac{1}{4}, x=\frac{1}{2} \\ lub\\x^{2} =-\frac{1}{4}, x=-\frac{1}{2} \\[/tex]
[tex]c)x^{4}-25=0\\ x^{4}=25\\ x^{2} =5,x=\sqrt{5} \\lub\\x^{2} =-5, x=-\sqrt{5}[/tex]
