Encuentra todos los factores de los siguientes polinomios haciendo uso de isión sintética. \( P(x)=x^{4}-5 x^{3}-7 x^{2}+41 x-30 \) \( P(x)=x^{4}+4 x^{3}-21 x^{2}+4 x+28 \) \( P(x)=4 x^{4}-8 x^{3}-3 x^{2}+7 x-2 \)

7. Factorise each of the following. (a) \( -x^{2}+5 x-6 \) (b) \( -x^{2}+7 x+8 \) (c) \( -2 x^{2}-11 x-5 \) (d) \( -3 x^{2}-11 x+4 \)

8. Factorise each of the following expressions. (a) \( x(x-5)+6 \) (b) \( x^{2}+3(x-6) \) (c) \( (x-3)^{2}+12 x \) (d) \( (x+3)(x-4)-8 \) (e) \( (3 x-4)(2 x-5)+8(2 x-5) \) (f) \( (3 x-4)^{2}-(2 x+1)^{2} \)

11. \( y-7=-10 \)

56. Вычислите значение выраже \( \frac{\sqrt{5}+\sqrt{7}}{\sqrt{5}-\sqrt{7}}+\frac{\sqrt{5}-\sqrt{7}}{\sqrt{5}+\sqrt{7}} \).

10. \( \frac{7 x+65}{5}=6 \)