In a is equal to
a2
c2
b2
a2 + b2
B.
c2
In a , the correct formulae among the following are
only I, II
only II, III
only I, III
I, II, III
An aeroplane flying with uniform speed horizontally one km above the ground is observed at an elevation of 60°. After 10 s if the elevation is observed to be 30°, then the speed of the plane (in km/h) is
E1 : a + b + c = 0, if 1 is a root of ax2 + bx + c = 0, E2 : b2 - a2 = 2ac, if are the roots of ax2 + bx + c = 0 Which of the following is true ?
E1 is true, E2 is true
E1 is true, E2 is false
E1 is false, E2 is true
E1 is false, E2 is false