Question

o valor de
$\sqrt{15 - \sqrt{32 + \sqrt{25 \: } }} - \sqrt{81}$
é:

a)1
b)2
c)3
d)4

Answer 1

$\sqrt{15- \sqrt{32+ \sqrt{25- \sqrt{81} } }} } = \\ \\ \sqrt{15- \sqrt{32+ \sqrt{25-9} } } = \\ \\ \sqrt{15- \sqrt{32+ \sqrt{16} } } = \\ \\ \sqrt{15- \sqrt{32+4} } = \\ \\ \sqrt{15- \sqrt{36} } = \\ \\ \sqrt{15-6} = \\ \\ \sqrt{9} =\fbox{ 3 } \\ \\ Letra~~C$