Let A1A2 intersect ω at A3. Consider the common tangent of circles ω and ωA passing through A2 and let U be a point on this common tangent which is at the same side of the line A1A2 with respect to B. Then by tangency, we have ∠A1A2U=∠BA1A2 and ∠BA2U=∠BA3A2. Therefore
∠CA2A3=∠A3BC=∠BA1A2−∠BA3A2=∠A1A2U−∠BA2U=∠BA2A1=∠A3CB
which means that A3B=A3C. By the sine law, we obtain that
A1CA1B=A3CA3B⋅sin∠CA3A2sin∠BA3A2=sin∠CA3A2sin∠BA3A2
and since ∠BAA2=∠BA3A2 and ∠CAA2=∠CA3A2, we obtain that
A1CA1B=sin∠CAA2sin∠BAA2
Similarly, we get
B1AB1C=sin∠ABB2sin∠CBB2andC1BC1A=sin∠BCC2sin∠ACC2
Therefore, we have
A1CA1B⋅B1AB1C⋅C1BC1A=sin∠CAA2sin∠BAA2⋅sin∠ABB2sin∠CBB2⋅sin∠BCC2sin∠ACC2

Since AA1,BB1,CC1 are concurrent, by Ceva Theorem, we have
A1CA1B⋅B1AB1C⋅C1BC1A=1
and hence
sin∠CAA2sin∠BAA2⋅sin∠ABB2sin∠CBB2⋅sin∠BCC2sin∠ACC2=1
which means that the lines AA2,BB2,CC2 are also concurrent by the Converse Trigonometric Ceva Theorem.