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sin2A=2sinA is true when A= 0o (b) 3...

`sin2A=2sinA` is true when `A=` `0o` (b) `30o` (c) `45o` (d) `60o`

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Two equal circles touch each other externally at C and A B is a common tangent to the circles. Then, /_A C B= 60o (b) 45o (c) 30o (d) 90o

In an isosceles triangle ABC if AC=BC and AB^(2)=2AC^(2), then /_C=30o(b)450 (c) 90o(d)60o

In Fig.10.96 ,if TP and TQ are tangents drawn from an external points T to a circle with centre O such that /_TQP=60o ,then /_OPQ=( FIGURE) 25o (b) 30o (c) 40o (d) 60o

If PT is tangent drawn from a point P to a circle touching it at T and O is the centre of the circle,then /_OPT+/_POT=30o (c) 60o( c) 90o (d) 180o

If the area of a sector of a circle is 5/(18) of the area of the circle, then the sector angle is equal to (a) 60o (b) 90o (c) 100o (d) 120o

The angle of intersection of the curves x y=a^2 and x^2-y^2=2a^2 is zero 0o (b) 45o (c) 90o (d) 30o

PQ is a tangent to a circle with centre O at the point P. If OPQ is an isosceles triangle, then /_OQP is equal to 30o (b) 45o(c)600 (d) 90o

If ABC and DEF are similar triangles such that /_A=47o and /_E=83o, then /_C=50o(b)60o(c)70o(d)80o

Through what angle does the minute hand of a clock turn in 5 minutes? 30o (b) 32o(c)35o (d) 36o

If tangents PA and PB from a point P to a circle with centre O are inclined to each other at an angle of 80o then /_POA is equal to 50o (b) 60o(c)70o (d) 80o

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  13. (1-tan^2 45o)/(1+tan^2 45o) is equal to tan90o (b) 1 (c) sin45o (d) si...

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  14. sin2A=2sinA is true when A= 0o (b) 30o (c) 45o (d) 60o

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  15. (2tan30o)/(1-tan^2 30o) is equal to cos60o (b) sin60o (c) tan60o (d) s...

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  16. If A, B and C are interior angles of a triangle ABC, then show that "s...

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