(21)/(4)q=3+sqrt(8)da^(2)+(1)/(a^(2))" in "

If the angle betweenthe lines whose direction cosines are (-(2)/(sqrt(21)), (C )/(sqrt(21)), (1)/(sqrt(21))) and ((3)/(sqrt(54)), (3)/(sqrt(54)), -(6)/(sqrt(54))) is (pi)/(2) , then the value of C is

The shortest distance between line y-x=1 and curve is : (1)(sqrt(3))/(4) (2) (3sqrt(2))/(8) (3) (8)/(3sqrt(2))(4)(4)/(sqrt(3))

P=(124-32sqrt(15))^((1)/(4)),q=(x^(4)+(1)/(x^(4))) where x=sqrt(3+2sqrt(2)), then ((q-p^(2))/(sqrt(15))) is

If the angle between the lines whose direcrtion cosines are (-(2)/(sqrt(21)),(C)/(sqrt(21)),(1)/(sqrt(21)))and((3)/(sqrt(54)),(3)/(sqrt(54)),(-6)/(sqrt(54))) is (pi)/(2) , then the value of C is

The value of cos^(2)48^(@)-sin^(2)12^(@) is ........... A) (sqrt5-1)/( 4) B) (sqrt5+1)/(8) C) (sqrt3-1)/(4) D) (sqrt3+1)/(2sqrt2)

If x = [-(q)/(2) + sqrt((q^(2))/(4) + (p^(3))/(27))]^((1)/(3)) + [-(q)/(2) - sqrt((q^(2))/(4) + (p^(3))/(27))]^((1)/(3)) then prove that x^(3) + pq + q = 0

A=(1,3,-2) is a vertex of triangle ABC whose centroid is G=(-1,4,2) then length of median through A is sqrt(21) 3sqrt(21) sqrt(21)/2 (3sqrt(21))/(2)