At the top, the VCC has arrows on it. What does that mean?
I thought it would be like in other circuits as empty holes that you could attach, but I'm not sure here.
Electronic – What does the arrow on VCC in a BJT bias circuit mean
bjt
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The DC analysis isn't that difficult.
EDIT: I see a far simpler analysis:
\$I_{B1} = \dfrac{V_{C1} - V_{BE2} - V_{BE1}}{R_2 + P_2}\$
\$V_{C1} = 9V - I_{C1} \cdot R_3 = 9V - \beta I_{B1} \cdot R_3\$
\$ \rightarrow I_{B1} = \dfrac{9V - V_{BE2} - V_{BE1}}{R_2 + P_2 + \beta R_3}\$
Now:
\$I_{E2} \approx \dfrac{V_{C1} - V_{BE2}}{R1}\$
\$V_{C2} = 9V - I_{C2} \cdot R_4 \$
Assume a value for the base-emitter voltages and P2 ,solve for the collector currents and check for active/saturation operation.
Here is a unconventional explanation (you can find many other conventional explanations on the web)...
The basic idea is to oppose two current sources (transistor collectors); so we have to connect them in the same loop and to vary their currents in opposite directions:
As a result the voltage of the common point between the sources will "move" extremely vigorously (a fully geometrical phenomenon):
A good example of this configuration is the classic CMOS stage where the two transistors are connected with their sources to Vdd and Vss (ground) and their drains are joined:
But in the emitter-coupled (long-tailed) pair, the collectors of both transistors (T1 and T2 below) are turned up. So, we should turn the one collector (the T1's in this example) back down to stand against the other (T2's) collector. For this purpose, we have connected the simple current mirror (T3-T4) in the picture below:
See also this paper and its more sophisticated version.
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Best Answer
The arrows have no special pointing significance. The conventional symbols used on schematics include the use of the arrow as a symbol for a power supply connection.
If you look around you will notice that there are a variety of different symbols used for power supply connections on schematics. There are also various ways that the associated voltage rail are labeled. Here is a sample of some of the common types. Note that in my example there is no particular correspondence between the label type and the symbol used. This is by no means an exhaustive list either and you can find other usages as well.