(b) Giải hệ bất phương trình \( \left\{\begin{array}{l}x^{2}-5 x+4 \geq 0 \\ x^{4}<81 \\ x^{3}-2 x^{2}+3 x-2 \leq 0\end{array}\right. \)

e. Qual i o valor de \( x \) \( \begin{array}{ll}\text { a) } 2^{x}=32 & \text { b) } 5^{x}=25\end{array} \)

2 - Qual é o valor de \( x \) \( \begin{array}{ll}\text { a) } 2^{x}=32 & \text { b) } 5^{a}=25\end{array} \)

Determina la función usan \( f(x)=\frac{7 x-3}{2} \) - Resuelue la

10. a. Show that the roots of the equation \( 2\left(a^{2}+b^{2}\right) x^{2}+2(a+b) x+1=0 \) can never be real unless \( a=b \). b. Prove that the roots of the equation \( x^{2}+(2 k-1) x+k^{2}=0 \) are real roots if \( k \leq \frac{1}{4} \).

Diberikan polinomial \( P(x)=x^{3}-5 x^{2}+4 x+4 \) \( Q(x)=-x^{2}-7 x+9 \) Nilai dari \( P(x)-Q(x)=\cdots \) A. \( \quad x^{3}-6 x^{2}-3 x+13 \) B. \( x^{3}-6 x^{2}-2 x+13 \) C. \( x^{3}+6 x^{2}-3 x+13 \) D. \( x^{3}+6 x^{2}-2 x+13 \) E. \( \quad x^{3}+6 x^{2}+3 x+13 \)