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To calculate the DC voltages at the terminals of transistors \( Q_1 \) and \( Q_2 \), we need to apply the principles of transistor operation and analyze the given circuit.

Here’s the step-by-step approach:

### 1. **Identify Key Components**:
   - \( V_{CC} = 10 \, \text{V} \) (the supply voltage).
   - \( R_1 = 33 \, \text{k}\Omega \), \( R_2 = 22 \, \text{k}\Omega \), \( R_E = 1.5 \, \text{k}\Omega \).
   - \( \beta_{Q_1} = \beta_{Q_1 \, \text{sat}} = 150 \) (DC current gain of \( Q_1 \)).
   - \( \beta_{Q_2} = \beta_{Q_2 \, \text{sat}} = 100 \) (DC current gain of \( Q_2 \)).

### 2. **DC Analysis of the Transistor Circuit**:
We'll assume the transistors are operating in the active region unless otherwise indicated.

#### a) **Voltage at the Emitter of \( Q_2 \)**:
The emitter resistor \( R_E = 1.5 \, \text{k}\Omega \) is connected to ground, and assuming \( V_{BE2} \) (the base-emitter voltage of \( Q_2 \)) is approximately 0.7V (a common assumption for silicon BJTs), the voltage at the emitter of \( Q_2 \) is given by the base voltage minus \( V_{BE2} \).

Let’s call the emitter voltage of \( Q_2 \), \( V_E2 \).

\[ V_E2 = V_{\text{sat}} - 0.7 \, \text{V} \]

Since \( V_{\text{sat}} \) is not directly provided in the diagram, but the presence of the emitter resistor means this voltage will be dependent on the current \( I_E \).

#### b) **Voltage at the Collector of \( Q_1 \)**:
The collector voltage of \( Q_1 \), \( V_{C1} \), will be primarily determined by the current flowing through \( R_1 \) and the supply voltage \( V_{CC} \). If we assume that the current through \( Q_1 \) is primarily determined by \( \beta_{Q_1} \), and the collector current \( I_{C1} \) is given by:

\[ I_{C1} = \beta_{Q_1} \cdot I_{B1} \]

where \( I_{B1} \) is the base current of \( Q_1 \), the collector voltage is:

\[ V_{C1} = V_{CC} - I_{C1} \cdot R_1 \]

#### c) **Voltage at the Base of \( Q_1 \) and \( Q_2 \)**:
Given the resistive divider formed by \( R_2 \) and \( R_1 \), the base voltage of \( Q_1 \), \( V_{B1} \), can be determined by:

\[ V_{B1} = \frac{V_{CC} \cdot R_2}{R_1 + R_2} \]

The base voltage of \( Q_2 \) depends on the small signal applied at \( V_{\text{in}} \) and the potential divider formed by \( R_E \).

### Conclusion:
To fully calculate the DC voltages at each terminal of \( Q_1 \) and \( Q_2 \), we would need either the specific values of \( V_{\text{sat}} \) or assumptions about small signal input. We know:

- \( V_{E2} \approx V_{\text{sat}} - 0.7 \, \text{V} \).
- \( V_{B1} \) is derived from the resistive divider \( R_1 \) and \( R_2 \).
- \( V_{C1} = V_{CC} - I_{C1} R_1 \).

Do you want further details on any specific voltage, or should I perform more detailed calculations based on typical assumptions? Let me know.

### Follow-up Questions:
1. What is the significance of \( \beta \) in determining the collector current of a transistor?
2. How would you calculate \( I_{C2} \) (collector current of \( Q_2 \)) based on the given resistances?
3. What would happen to the circuit if \( \beta \) of the transistors increased?
4. Can you explain the purpose of the capacitor \( C \) in the circuit?
5. How does the input AC signal influence the operation of the transistors in the circuit?

### Tip:
Always verify the operation region (active, saturation, or cutoff) of transistors to ensure your calculations match the actual circuit behavior.

Detailed analysis of the DC voltages at the terminals of transistors Q1 and Q2 in a BJT circuit. Learn the steps to calculate the base, collector, and emitter voltages using voltage division, transistor gain (β), and Ohm's Law.

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