Question

Решите, 8 и 9 задание подробно!

Answer 1

8. $a^{2}-b^{2} = (a-b)*(a+b)$

=(764,57-235,43)*(764,57+235,43) = 529,14*1000 = 529140

9. $(a-b)*(a+b)= a^{2}-b^{2}$ ; $(a+b)^{2}= a^{2}+2ab+b^{2}$

$(\frac{1}{25}a^{4}-\frac{1}{4}b^{4}) - (\frac{1}{25}a^{4}+2*\frac{1}{10} a^{2}b^{2} +\frac{1}{4}b^{4})=-\frac{1}{5} a^{2}b^{2} -\frac{1}{2}b^{4}$