It is known that: three points a (a, 1), B (3, 1), C (6, 0), point a is on the image of positive scale function y = 12x. (1) find the value of a; (2) point P is a moving point on X axis. ① when the sum of △ OAP and △ CBP circumference reaches the minimum, find the coordinates of point p; ② when ∠ APB = 20 °, find the degree of ∠ OAP + ∠ PBC

It is known that: three points a (a, 1), B (3, 1), C (6, 0), point a is on the image of positive scale function y = 12x. (1) find the value of a; (2) point P is a moving point on X axis. ① when the sum of △ OAP and △ CBP circumference reaches the minimum, find the coordinates of point p; ② when ∠ APB = 20 °, find the degree of ∠ OAP + ∠ PBC

(1) ∵ point a (a, 1) is on the image of positive scale function y = 12x, and ∵ a = 2. (2) as shown in Fig. 1, a ′ (2, - 1) can be obtained by making point a ′, which is symmetric about x-axis. Connect a ′ B with X-axis at point P. suppose that the analytic expression of line a ′ B is y = KX + B (K ≠ 0), then the analytic expression of line a ′ B is y = 2x-5. When y = 0, x = 2.5. When AP + BP gets the minimum value, the relationship between the perimeter of △ OAP and △ CBP can be obtained (2) as shown in Figure 2, let AA 'intersect the x-axis at point K. connect OA', OB and AB, and make BM ⊥ OC at M. ∵ a 'k = AK = AB = 1, ∠ Oka' = ∠ a 'AB = 90 °, OK = AA' = 2, ≌ a 'ab. (4 points) ≌ OA' = a 'B, ≌ OA' k = ∠ ABA ' The △ OA ′ B is isosceles right triangle. ℅ boa ′ = ∠ BOC + ∠ a ′ OC = 45 °. ∵ BM ⊥ OC, OM = MC = 3, ∵ ob = BC. 〉 BOC = ∠ BCO. ∵ AOC = ∠ a ′ OC, ∵ AOC + ∠ BCO = 45 °. As shown in Figure 3, when ∠ APB = 20 °, the ∠ OAP + ∠ PBC = 360 ° - (∠ AOC + ∠ BCO) - (∠ apo + ∠ BPC) = 360 ° - 45 ° - (180 ° - 20 °) = 155 °

It is known that y is a positive proportional function of X. when x = 2, y = half, find the function value when x = - 3

Because when x = 2, y = half;
So x = 4Y;
When x = - 3, y = - 3 / 4

Is the second power of y = X-1 a positive scale function? Is y = negative half? Is x a positive scale function?

For example, y = KX (k cannot be 0) is a positive proportion function, so the first one is not and the second one is

1. Positive scale function y = half X image passes through point (,) (,) 2. Image of straight line y = half x + 3 passes through point (,) (,)
3. Given that the line y = KX + B satisfies the condition that y increases with the increase of X, then ()
4. The focus coordinates of y = 2x + 1 and y = X-2 are (,)
5. The intersection coordinates of x-axis and Y-axis of the image with the function y = 2x-6 (,)
How to do these questions sit and wait for a function

1. The positive scale function y = half x, the image passes through the point (0,0) (2,1) 2. The image of the line y = half x + 3 passes through the point (0,3) (2,4) 3