Given that the inverse function of the function y = 2x-a is y = BX + 3, then a=______ ;b=______ .

Given that the inverse function of the function y = 2x-a is y = BX + 3, then a=______ ;b=______ .

Method 1: the inverse function of function y = 2x-a is y = 12x + 12a. Compared with y = BX + 3, we can get a = 6, B = 12. Method 2: take point (0, 3) on y = BX + 3, and get point (3, 0) on Y = 2x-a, so we can get a = 6. If there is a point (0, - 6) on y = 2x-6, then point (- 6, 0) on y = BX + 3 can get a = 6, B = 12. Answer: a = 6; b = 12