The set of all values of a for which the function f(x)=(a²-3a+2)(cos²x/4-sin²x/4)+(a-1)x+sin 1 does not possess critical points is

The least value of (x-a) (x-b) occurs at x=

F(x)= tan^-1 x is

The approximate value of  4√80 is

The curve whose subtangent is twice the abscissa of the point of contact and passing through (1,2) is

The subnormal to the curve y=a^x at any point varies directly as

If the tangent at the point (at², at³) on the curve ay²=x³ meets the curve again at Q, then Q=

The angle between the curves y²=x, x²=y at (1, 1) is

The function f(x)=√9-x² is increasing in

The point on y=x²+7x+2 which is closest to the line y=3x-3 is