confusion

what is the difference in these two statements....

>> a point dividing a line internally
>> a point dividing a line externally

let us suppose P divides AB in the ratio m:n and A = (x1,y1), B = (x2,y2)

then coordinates of P in each case

1 Answers

(Internal)\; \left(\frac{mx_2+nx_1}{m+n}, \frac{my_2+ny_1}{m+n}\right)\\ (External) \left(\frac{mx_2-nx_1}{m-n}, \frac{my_2-ny_1}{m-n}\right)

P divides AB internally in ration m:n, means APPB = mn

Q divides AB externally in ration m:n, means AQQB = mn

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