Find c so that these vectors are mutually perpendicular:

a = <c,−2, 3> and b = <c, c,−5>.

how would you go about doing this.

I know how to apply the cross product.

Printable View

- Mar 30th 2011, 02:08 AMrealisticFind so that these vectors are mutually perpendicular
Find c so that these vectors are mutually perpendicular:

a = <c,−2, 3> and b = <c, c,−5>.

how would you go about doing this.

I know how to apply the cross product. - Mar 30th 2011, 02:10 AMProve It
Two vectors are perpendicular if their dot product is $\displaystyle \displaystyle 0$.

- Mar 30th 2011, 02:19 AMrealistic
thanks for response and yes i agree if its 0 its mutually perpendicular.

would i have to put a = <c,−2, 3> and b = <c, c,−5> into its determinant form then solve? - Mar 30th 2011, 02:30 AMProve It
No, take the dot product and set it equal to $\displaystyle \displaystyle 0$. Then solve the resulting quadratic.

- Mar 30th 2011, 02:48 AMrealistic
ok i see

i got an answer of −3 or it could be 5 i think that's correct - Mar 30th 2011, 03:34 AMPlato
Yes that is correct.