प्रश्नाबानी 2.2 निम्न द्विघात बहुपदों के शून्यक ज्ञात कीजिए और शून्यकों तथा गुणांकों के बीच के संबंध की सत्यता की जाँच कीजिए : \( \begin{array}{lll}\text { (iv) } x^{2}-2 x-8 & \text { (ii) } 4 s^{2}-4 s+1 & \text { (iii) } 6 x^{2}-3-7 x \\ \text { (iv) } 4 u^{2}+8 u & \text { (v) } s^{2}-15 & \text { (vi) } 3 x^{2}-x-4\end{array} \)

42. Julio paid \( 7 \frac{3}{4} \% \) sales tax on an item he bought. He figured that if he had bought the item in a neighboring state where the sales tax is \( 8 \frac{1}{4} \% \), he would have paid \( \$ 75 \) more. What was the cost of the item before tax? (C) \( \$ 15,000.00 \) (IS) \( \$ 3,750.00 \) (C) \( \$ 1,500.00 \) (D) \( \$ 150.00 \) (F) \( \$ 37.50 \)

f) \( (-15 a b c+12 a b-9 a c-3 a) \div(-3 a) \)

(Express \( \frac{6}{7 h}-\frac{3-4 g}{14 h} \) as a single fraction in its simplest form. Ungkapkan \( \frac{6}{7 h}-\frac{3-4 g}{14 h} \) sebagai pecahan tunggal dalam bentuk termudah.

3.18. Determine el máximo comun divisor de los enteros \( 15,18,24 \) y escríbalo como una combinación lineal de \( 15,18,24 \). 3.19. Sea \( a \in \mathbb{Z}^{+} \)tal que \( \operatorname{mcd}(240, a)=1 \), probar que \( 240 \mid a^{4}-1 \).

-простіть вираз: \( \begin{array}{ll}15 \mathrm{~m}^{2} \cdot\left(4 \mathrm{~m}^{3}\right)^{2} ; & \text { 2) }-0,5 \mathrm{~m}^{5} \cdot\left(2 \mathrm{~m}^{3}\right)^{4} \\ \left.-3 \mathrm{a}^{3} \mathrm{~b}^{4}\right)^{4} \cdot\left(-\frac{1}{8} a^{3} b\right) ; & \text { 4) }\left(-\frac{4}{5} m n^{4}\right)^{3} \cdot 25 m^{4} \mathrm{n}\end{array} \)