Given the linear function y = KX + B, when 0 ≤ x ≤ 2, the value range of the corresponding function value y is - 2 ≤ y ≤ 4, then the value of KB is () A. 12b. - 6C. - 6 or - 12D. 6 or 12

Given the linear function y = KX + B, when 0 ≤ x ≤ 2, the value range of the corresponding function value y is - 2 ≤ y ≤ 4, then the value of KB is () A. 12b. - 6C. - 6 or - 12D. 6 or 12

(1) When k ＞ 0, y increases with the increase of X, that is, the first-order function is an increasing function, when x = 0, y = - 2, when x = 2, y = 4, substituting into the analytic formula of first-order function y = KX + B, B = − 22K + B = 4, the solution is k = 3B = − 2, KB = 3 × (- 2) = - 6; (2) when k ＜ 0, y decreases with the increase of X, that is, the first-order function is a decreasing function, when x = 0, y = 4, when x = 2, y = - 2, substituting into the first-order function The analytic formula of function y = KX + B is: B = 42K + B = − 2, the solution is k = − 3B = 4, ｜ KB = - 3 × 4 = - 12. So the value of KB is - 6 or - 12. So choose C