Position Vectors

creatively12 · #1 $Old$ October 13th, 2009, 02:08 PM

C is the point on AB such that AC:CB = 4:3. Express c in terms of a and b

Please help !!!

Plato · #2 $Old$ October 13th, 2009, 02:31 PM

Quote:

Originally Posted by creatively12 $View Post$

C is the point on AB such that AC:CB = 4:3. Express c in terms of a and b

What kind course are you doing?
Are there no notes or text book?
These questions are so fundamental, you should have no trouble with them.

$c=a+\frac{4}{7}(b-a)$

creatively12 · #3 $Old$ October 13th, 2009, 02:36 PM

thanks for your help, m doing A levels, yes there is a textbook but its not good, and m not that good with vectors actually.

but the answer to this question is c = (3/7)a + (4/7)b

Plato · #4 $Old$ October 13th, 2009, 03:22 PM

Quote:

Originally Posted by creatively12 $View Post$

but the answer to this question is c = (3/7)a + (4/7)b

You are not doing anything for yourself!
Had you, you would have seen
$c=a+\frac{4}{7}(b-a)=\frac{4}{7}b+\frac{3}{7}a$ .

You must do more for yourself. That is the only way to learn mathematics.