Question

calculati:                                          rog  raspuns la fiecare operatie:)

Answer 1

$(1 \frac{1}{5} )^{2}- ( \frac{7}{10} )^{2}+ (1 \frac{1}{5}- \frac{7}{10} )^{2} =$
$=(1 \frac{1}{5} )^{2}- ( \frac{7}{10} )^{2}+(1 \frac{1}{5} )^{2} -2*1 \frac{1}{5} *\frac{7}{10}+( \frac{7}{10} )^{2}=$
$=2* (1 \frac{1}{5} )^{2} -2*(1 \frac{1}{5} )* \frac{7}{10}=$
$=2* ( \frac{6}{5} )^{2} -2* \frac{6}{5}* \frac{7}{10} =$
$=2* \frac{36}{25} -2* \frac{42}{50} =$
$= \frac{72}{25} -\frac{84}{50} = \frac{144-84}{50}= \frac{60}{50} = \frac{6}{5}$