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Question
"Find the acute angle between the tangents to the circle
x^2+y^2-2x+8y-23=0 from the point (8,-3)"
Questioner: Dhananjay
Country: United States
Category: Advanced Math
Private: No
Subject: Maths-Circle
Question: "Find the acute angle between the tangents to the circle
x^2+y^2-2x+8y-23=0 from the point (8,-3)"
Start this with the same type of diagram as in the last question.
1. Complete the square to get C, r for the circle.
2. Mark your P1 and P2.
3. Determine CP1 and Cp2.
4. Call (8,-3) point Q and find CQ.
5. Now use some trigonometry.
If you get stuck, send me what you did and I'll see if I can help.
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Answers by Expert:
Paul Klarreich
Expertise
I can answer questions in basic to advanced algebra (theory of equations, complex numbers), precalculus (functions, graphs, exponential, logarithmic, and trigonometric functions and identities), basic probability, and finite mathematics, including mathematical induction. I can also try (but not guarantee) to answer questions on Abstract Algebra -- groups, rings, etc. and Analysis -- sequences, limits, continuity. I won't understand specialized engineering or business jargon.
Experience
I taught at a two-year college for 25 years, including all subjects from algebra to third-semester calculus.
Education/Credentials
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