From a point $P$ outside a circle draw two tangents

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From a point $P$ outside a circle, draw two tangents to the circle touching at points $A$ and $B$. Draw a sectant line intersecting the circle at points $C$ and $D$, with $C$ between $P$ and $D$. Choose point $Q$ on the chord $CD$ such that $\angle DAQ=\angle PBC$. Prove that $\angle DBQ=\angle PAC$.

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I have somehow made a figure but could not solve it. Please help me with this..

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Let O be the center of the circle ACBD.

enter image description here

Fact-1: All the same color coded angles are equal.

Fact-2: The red dotted circle will pass through A,P, B, O.

Fact-3: $\angle purple1 = \angle green + \angle red$, a standard result from tangent properties.

By considering $\triangle ADQ$, $\angle blue = \angle green + \angle red$.

Since $\angle purple1 = \angle blue$, we say that A, P, B, Q, O are con-cyclic.

Then, $\angle black = \angle purple2 = \angle purple1$

That means $\angle green + \angle yellow = \angle green + \angle red$.

Result follows.