Question

find the equation of tangents to the circle x2+y2=10 at the points whose abscissa is 1.

Answer 1

H^2=p^2+b^2 13^2=p^2+12^2 169-144=p^2 P=5  Area=1÷2×b×h         =1÷2×12×5         =30 cm^2

Answer 2

• The radius of the circle is v3.

• The two points are: +v2:1, -v2:1.

• If z is the angle of one of the tangents, then sin(z) = v2/v3 = v3/y,

• where y is the ordinate of one of the tangents.

• This tangent, therefore is the st line connecting the points (3/v2,0) and (v2,1).

• The other tangent is the line connecting the points (-3/v2,0) and (-v2,1).