AC is tangent to O, O'D is `_|_` to AC, Find the value of `(DO')/(CO)`

Find the value of cos(-60^o)

In the given figure, two equal circles with centres O and O' touch each other at X. OO' produced meets the circle with centre O' at A. AC is a tangent to the circle with centre O at the point C. O'D is perependicular to AC. Find the value of (DO')/(CO) .

. In the given figure, two equal circles, with centres O and O', touch each other at X. OO' produced me the circle with centre O' at A. AC is tangent to the circle with centreO, at the point C. O'D is perpendicular to AC. Find the value of (DO')/(CO).

. In the given figure, two equal circles, with centres O and O', touch each other at X. OO' produced me the circle with centre O' at A. AC is tangent to the circle with centreO, at the point C. O'D is perpendicular to AC. Find the value of (DO')/(CO) .

. In the given figure, two equal circles, with centres O and O', touch each other at X. OO' produced me the circle with centre O' at A. AC is tangent to the circle with centreO, at the point C. O'D is perpendicular to AC. Find the value of (DO')/(CO) .

Find the value of cos210^o

If cos O/ = 1/(sqrt2) , then find the value of 4 + cot O/ .