If x + y + z = 6 and x2 + y2 + z2 = 20, then the value of x3 + y3 + z3 - 3xyz is
64
70
72
76
In a ΔABC, the side BC is extended upto D. Such that CD = AC, if ∠BAD = 109° and ∠ACb = 72°, then the value of ∠BAC is
35°
60°
40°
45°
Two circles touch each other internally, Their radii are 2 cm and 3 cm. The biggest chord of the greater circle which is outside the inner circle is of length
2√2 cm
3√2 cm
2√3 cm
4√2 cm
D.
4√2 cm
From the figure,
MN is the diameter fo the smaller circle and PQ is the biggest chord of the greater circle. O is the centre of the greater circle and O' is the centre of the inner circle.
Now,
OM = MN - ON = 4 - 3 = 1 cm
Now,
In Δ PMO,
ABCD is a cyclic quadrilateral. AB and DC are produced to meet at P. If ∠ADC = 60°, then the ∠PBC + ∠PCB is
130°
150°
155°
180°
From a point P which is at a distance of 13 cm from centre O of a circle of radius 5 cm, in the same plane, a pair of tangents PQ and PR are drawn to the circle. Area of quadrilateral PQOR is
65 cm2
60 cm2
30 cm2
90 cm2
ABCD is a cyclic trapezium with AB || DC and AB a diameter of the circle. If ∠CAB = 30°, then ∠ADC is
60°
120°
150°
30°
ABC is a triangle. The bisectors of the internal angle ∠B and external angle ∠C intersect at D. If ∠BDC = 50° then ∠A is
100°
90°
120°
60°
AB is the chord of a circle with centre O and DOC is a line segment originating from a point D on the circle and intersecting AB produced at C such that BC = OD. If ∠BCD = 20°, then &angAOD is equal to
20°
30°
40°
60°