document.write( "Question 739955: Find the equation of the tangent at the point (0,3) on a circle of x sqr + y sqr = 1. \n" ); document.write( "
Algebra.Com's Answer #451454 by Alan3354(69443)![]() ![]() You can put this solution on YOUR website! Find the equation of the tangent at the point (0,3) on a circle of x sqr + y sqr = 1. \n" ); document.write( "------------- \n" ); document.write( "Use ^ (Shift 6) for exponents. \n" ); document.write( "x^2 + y^2 = 1 \n" ); document.write( "(0,3) is not on the circle. \n" ); document.write( "If you mean thru (0,3) and tangent to the circle: \n" ); document.write( "----- \n" ); document.write( "(0,3) is P and the tangent point is T \n" ); document.write( "O is the origin \n" ); document.write( "OTP is a right triangle with T = 90 degs \n" ); document.write( "side TP = sqrt(3^2 - 1^2) = sqrt(8) \n" ); document.write( "---- \n" ); document.write( "The tangent point is on the given circle and on the circle centered at (0,3) with radius sqrt(8) --> x^2 + (y-3)^2 = 8 \n" ); document.write( "--------- \n" ); document.write( "Find the intersections of the 2 circles (2 of them) \n" ); document.write( "x^2 + (y-3)^2 = 8 \n" ); document.write( "x^2 + y^2 = 1 \n" ); document.write( "----------------------- Subtract \n" ); document.write( "(y-3)^2 - y^2 = 7 \n" ); document.write( "y^2 - 6y + 9 - y^2 = 7 \n" ); document.write( "-6y = -2 \n" ); document.write( "y = 1/3 \n" ); document.write( "------- \n" ); document.write( "x = -sqrt(8)/3 --> (-sqrt(8)/3,1/3) \n" ); document.write( "x = +sqrt(8)/3 --> (+sqrt(8)/3,1/3) \n" ); document.write( "------------------ \n" ); document.write( "Find the eqn of the line thru the pairs of points \n" ); document.write( "--- \n" ); document.write( "|x y 1| \n" ); document.write( "|0 3 1| = 0 \n" ); document.write( "|sq 1/3 1| \n" ); document.write( "sq is the point (sqrt(8)/3,1/3) \n" ); document.write( "------------ \n" ); document.write( "In Quadrant 1: \n" ); document.write( "x*(3 - 1/3) - y*(0 - sqrt(8)) + (0 - sqrt(8)) = 0 \n" ); document.write( "8x/3 + sqrt(8)y = sqrt(8) \n" ); document.write( "-------------------------- \n" ); document.write( "You can find the other line. \n" ); document.write( " |