Which of the following statement(s) is/are 'CORRECT' ?

(A) Rolleís theorem is applicable to the function f(x) = 1 - 5√x^{6} in the interval [-1, 1]

(B) The value of

is equal to - 2

(C) If vector a and b are any two unit vectors, then least value of

is equal to 2.

(D) The angle between pair of tangents drawn to the curve e 7x^{2} - 12y^{2} = 84 from M(1,2) is π/4