As shown in the figure, (1) (2) Ca = CB, Da = dB, prove that CD is the vertical bisector of ab
CA=CB
AD=DB
CD=CD
∴△ACD≌△BCD
∴∠ACD=∠BCD
AC=BC
The bisector of the vertex angle of an isosceles triangle is perpendicular to the bottom and bisects the bottom
RELATED INFORMATIONS
- 1. It is known that, as shown in the figure, CA = CB
- 2. As shown in the figure, CA = CB, Da = dB
- 3. If a > b > C is known, it is proved by analysis or synthesis that 1 / (a + b) + 1 / (B-C) > = 4 / (A-C)
- 4. Given that a + B + C = 12, the square of a + the square of B + the square of C = 60, find the value of AB + BC + Ca, and ask for the help of God
- 5. Given that A-B = B-C = 3 / 4, the square of a + the square of B + the square of C = 1, what is the value of AB + BC + Ca
- 6. What is the reciprocal method
- 7. What is reciprocal
- 8. To prove x > y a < B and all of them are positive numbers to prove X / x + a > y / y + B requires seven solutions to do the difference method, the quotient method and the reciprocal method. I can prove the remaining four At least 5 solutions can add 100 points
- 9. It is known that a > b > 0, C > d > 0, a of B = C of D. it means that ① (a + b) / a = (c + D) / C. ② (a-b) / b = (C-D) / d Please use the eighth grade knowledge of Shandong education press to answer, thank you
- 10. Prove by definition: if a > b > 0, C
- 11. As shown in the figure, D is a point in the quadrilateral aebc, connecting AD and BD. it is known that Ca = CB, Da = dB and EA = EB. (1) are the three points c, D and E in a straight line? Why? (2) If AB = 24, ad = 13, CA = 20, what is the length of CD?
- 12. C. D is the point outside the line AB, and Ca = CB, Da = ab Please use the theorem of vertical bisector. No auxiliary line is allowed
- 13. If we know the line AB and the points c, D, and Ca = CB, Da = dB, then the line CD is the integral of the line ab______ .
- 14. It is known that C and D are points outside the line AB, and Ca = CB, Da = dB. It is proved that the straight line CD bisects AB vertically Prove with the vertical bisector of line segment
- 15. If two points c and D outside the line BC are known, CA = CB, Da = dB, and the straight line CD intersects AB at O, then point O is the midpoint of AB, and CD is the vertical bisector of ab
- 16. In space quadrilateral ABCD, ab ⊥ CD, BC ⊥ Da, prove: ab ^ 2 + CD ^ 2 = BC ^ 2 + Da ^ 2
- 17. If a > b > C, a + 2B + 3C = 0, AB > AC and ab
- 18. a. B is a non negative number √ (1-A ^ 2) √ (1-B ^ 2) = ab
- 19. It is proved that if a, B ∈ R, then at least one of a ^ 2 + AB and B ^ 2 + AB is non negative Good answer points
- 20. Known: 0 〈 a 〈 1, proof: 1 / a 4 / (1-A) greater than or equal to 9