Question

Решите пожалуйста 1 и 2

Answer 1

1
1)0,25-1,09=-0,84
2)-0,84*1,25=-1,05
3)18,9-16,65=2,25=2 1/4
4)2 1/4(8/9=9/4*8/9=2
5)-1,05:2=-0,525
2
√x/(√x-√y)-√y/(√x+√y)=(x+√(xy)-√(xy)+y)/(x-y)=(x+y)/(x-y)

Answer 2

$1) \frac{(0,29-1,09)*1,25}{(18,9-16 \frac{13}{20} )* \frac{8}{9} } = \frac{-0,8*1,25}{(18,9-16,65 )* \frac{8}{9} }= \frac{-1*9}{2,25*8} =\\= \frac{-9}{18} =-0,5\\2) \frac{ \sqrt{x}}{ \sqrt{x} - \sqrt{y} } - \frac{ \sqrt{y} }{ \sqrt{x} +\sqrt{y} } = \frac{ \sqrt{x}( \sqrt{x} + \sqrt{y} )- \sqrt{y}( \sqrt{x} - \sqrt{y)} }{( \sqrt{x} - \sqrt{y}) ( \sqrt{x} + \sqrt{y} ) }=\\= \frac{x+ \sqrt{xy} - \sqrt{xy} +y}{x-y} = \frac{x+y}{x-y}$