Current location - Training Enrollment Network - Mathematics courses - Ningbo 2 1 Math Answers for Senior High School Entrance Examination
Ningbo 2 1 Math Answers for Senior High School Entrance Examination
involve

(1) Let the coordinate origin be o ˊ, and the circle o intersects the X axis at G, connecting DB, DG and FG; ∠ CDG =∠ CBA = 45 is inscribed by the quadrilateral DGBP into the circle O, ∠ C = ∠ CBD = ∠ DFG is vertically divided by the DC = DB of CB, and it can be deduced that the diameter DF is ∠ DGF = 90 =∞.

(2) Let PH⊥x axis be in H, and Y axis be in ⊥x axis, ∴ph∨y axis;

(1) If point D is between O and A on the Y axis, ∠ DFB = ∠ DGB = ∠ CDG+∠ C = 45+∠ C ∠ BDF ∴ can only be BD ∶ BF = 2 ∶ 656. . OC = 2, ∴ XP = 2, YP = 2+4 = 2, namely P (2 2,2);

② If point D is above A on the Y axis, ∠DC = db =∠dfe+∠efb = 45+∠efb∠BDF∴ can only be BD ∶ BF = 2 ∶ 1, which is vertically divided by DO. OC = 2, ∴ XP =-2, YP =+2+4 = 6, that is, P (-2,6);

(3) If point D is below O on the Y axis, ∠ DC = DB = ∠ BPC = ∠ ABC-∠ BCP = 45-∠ BCP ∠ BDF ∴ can only be BD ∶ BF = 1. ∴ o ˊ h = 2oc = 8, ∴ XP = 8, YP = 8+4 = 4, that is, P (8,4);

The coordinate of the comprehensive point P is (2,2) or (-2,6) or (8,4).