Zadaci:$$ $$ a) $$ 9 X + 21 x^2 + 5x - 3 = 0$$ b) $$ 4x^2 - 9 x + 9 = 0$$ c) $$x^2 + 4x + 4 9 X^{2} - \frac{ x - 6 }{\ x ^{2}+ 3 x-3}= -{ 9\over \sqrt{x^5}}+ x - 55 0$$ d) $$3x^2 - 6x + 2 = 9 $$ e) $$ 9 X^{2}-\frac{1}{ 9 } X^{3} = 0 $$ f) $$ f(x) = { 8 x^{-3/ 9 }} \implies {dy \over dx} $$ g) $$ \binom{21}{x}\sum_{x}^{x+12} ( X+2X - 11 ) $$ h) $$ X^{3} - 11 X - 11 + 8 X^{2}-\frac{1}{ 9 } Y^{2} = 0 $$ i) $$ 21 \cdot x^{3} - \frac{x^{2}- 9 \cdot x+3}{x^{2}-1}+4 = 21 $$