MathematicsEasy175×since 2002Q2708Let f(x) = xa2+x2−d−xb2+(d−x)2, {x \over {\sqrt {{a^2} + {x^2}} }} - {{d - x} \over {\sqrt {{b^2} + {{\left( {d - x} \right)}^2}} }},\,\,a2+x2x−b2+(d−x)2d−x, x ∈\, \in∈ R, where a, b and d are non-zero real constants. Then :Af is an increasing function of xBf is neither increasing nor decreasing function of xCf ' is not a continuous function of xDf is a decreasing function of xCheck answerSkip