\( \frac{2}{\sqrt{3}-\sqrt{2}} \) ifadasinin moxracini irasionalliqdan azad edin.

3. ( 0,5 điểm) Tìm \( x \) biết: \( x^{2}(x-1)+4=4 x \)

\( \frac { 1 } { r } \times \frac { 1 - ( \frac { 1 } { r } ) ^ { n } } { 1 - \frac { 1 } { r } } \geq \frac { 9 r } { 100 } \Rightarrow 1 - \frac { 1 } { r ^ { n } } \geq \frac { 9 r } { 100 } \)

\( \frac { 1 } { r } x \frac { 1 - ( \frac { 1 } { r } ) ^ { n } } { 1 - \frac { 1 } { r } } \geq \frac { 9 r } { 100 } \Rightarrow 1 - \frac { 1 } { r ^ { n } } \geq \frac { 9 r } { 100 } \)

Given that the quadratic equation \( p x^{2}-9 q x+9 p=0 \), where \( p \) and \( q \) are constants, has two equal roots. Find \( p: q \). [2 marks.

(c) Subtract: \( 31(1-4 m+5 n) \) from \( 4 I(10 n-3 m+21) \) (d) Subtract: \( 3 a(a+b+c)-2 b(a-b+c) \) from \( 4 c(-a+b+c \)