Mathematics Test - 8

A mirror and a source of light are situated at the origin O and at a point on OX respectively. A ray of light from the source strikes the mirror and is reflected. If the direction ratios of the normal to the plane are proportional to 1, –1, 1 then direction cosines of the reflected ray are

If one root of the equationax²+ bx + c = 0 be n times the other root, then

The coefficient of x in the equationx²+ px+ q = 0 was taken as 17 in place of 13, its roots were found to be -2 and -15, the roots of the original equation are

If the sum of two of the roots ofx³+px²+qx+r=0is zero, then pq =

In a town of 10,000 families it was found that 40% family buy newspaper A, 20% buy newspaper B and 10% families buy newspaper C, 5% families buy A and B, 3% buy B and C and 4% buy A and C. If 2% families buy all the three newspapers, then number of families which buy A only is

Let n(U) = 700, n(A) = 200, n(B) = 300 and n(A ∩ B) = 100,

Then n(A^c∩B^c)=

If the sets A and B are defined as

A = {(x, y) : y =1/x, 0 ≠ x ∈ R}

B = {(x, y) : y = -x, x ∈ R}, then

If A and B are two given sets, then A ∩ (A∩B)^c is equal to