VIEỎT PHỬỤNG TRỠNH TIEỎP TUYEỎN CUỶA (C) ỦI QUA ỦIEỒM P(3, 1)

2) Vieỏt phửụng trỡnh tieỏp tuyeỏn cuỷa (C) ủi qua ủieồm P(3, 1):

A

ẹửụứng thaỳng (d) qua P coự heọ soỏ goực k:y = k( x-3) + 1

M

x+1 = k(x-3) + 1 (1)







B

x-1

 

O

x

-2 = k (2)



(x-1)

coự nghieọm





²

(d) tieỏp xuực (C)

Thay (2) vaứo (1) :

x







x

^

^x

²

^

¹

^

²⁽

^x

^

^{3) (}

^

^x

^

¹⁾

²

^

⁴

^x

^{ }

⁸

^x

^

²

1 (x-1)



1 -2(x-3) 1

²

Thay vaứo (2)

^

^k

^

²

Vaọy phửụng trỡnh tieỏp tuyeỏn ủi qua P laứ: y= -2x + 7