11) If \( \log _{3} 5=\mathrm{a} \), then \( \log _{15} 5= \) (a) \( a^{2} 3^{2}=5 \)

Find the factar of \( x^{5}+x^{4}-13 x^{3}-13 x^{2}+36 x+36 \) of list three facturs.

7. Show that the set F of the six complex valued functions: \( f_{1}(z)=z, f_{2}(z)=\frac{1}{1-z}, f_{3}(z)=\frac{z-1}{z} \) \( f_{4}(z)=\frac{1}{z}, f_{5}(z)=1-z, f_{6}(z)=\frac{z}{z-1} \) is a group under the usual multiplication of mappings.

\( \begin{array}{ll}7(y+3)-2(x+2)=14 & \text { Solve using subatitutio } \\ 4(y-2)+3(x+3)=2 & \text { methad }\end{array} \)

\( \sqrt { 5 } \quad \frac { \sqrt[ 3 ] { 5 ^ { x } \cdot 5 ^ { 2 } - x } } { \sqrt { 5 ^ { x + 1 } } } = 2 s ^ { 3 } \sqrt { 5 } \)

9. Show that (i) \( \binom{n+2}{2}-\binom{n}{2}=n+\frac{1}{2} \) Solution: