If the line `|y| = x -alpha`, such that `alpha > 0` does not meet the circle `x^2 + y^2 - 10x + 21 = 0`, then `alpha` belongs to

If the straight line y= x sin alpha + a sec alpha is a tangent to the circle x^(2) + y^(2) = a^(2) then-

If the line y cos alpha=x sin alpha+a cos alpha be a tangtnt to the circle x^(2)+y^(2)=a^(2) then

If the line y cos alpha = x sin alpha +a cos alpha be a tangent to the circle x^(2)+y^(2)=a^(2) , then

If the line y cos alpha = x sin alpha +a cos alpha be a tangent to the circle x^(2)+y^(2)=a^(2) , then

The line x sin alpha- ycos alpha = a touches the circle x^(2) +y^(2) =a^(2) ,then

A ray of light emanating from (-4, 3) after reflection from x-axis at (alpha, 0) is normal to circle x^2 +y^2 -10x-2y+25=0 , then 4alpha=

The line x sin alpha - y cos alpha =a touches the circle x ^(2) +y ^(2) =a ^(2), then,

The circle on the chord x cos alpha + y sin alpha -p= 0 of the circle x^2 + y^2 - 2 = 0 as diameter is: