2.Prove that (1/ tan^2θ +1 )+sin^2 = 1 is an identity.
3.ABEC is a sector with radius 2 cm. ABC is an equilateral triangle. If AE bisects ∠BAC,
(a) find the lengths of AE and DE.
(b) find ∠AEB and ∠DBE.
(c) by using the results of (a) & (b), find the value of tan15.
4.The lenth of a side of the rhombus ABCD is 16cm. If ∠DAC =30, find the lengths of the two diagonal.
5. ABCDEF is a trgular hexagon of sides 10 cm.
(a) Find the length of BF.
(b) Find the area of △BDF.
6. O is the centre of the base circle of the right circular cone VAB. If ∠OVB =30 , find the height and the volume of the cone.
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