## butterflyprincess 3 years ago Anyone good with VECTORS? PIC INCLUDED* Suppose that a box is being towed up an inclined plane as shown in the figure. Find the force w needed to make the component of the force parallel to the inclined plane equal to 2.5 lb. Give answer in component form.

1. butterflyprincess

2. hba

Pre Calculus

3. hba

I got it. Just take the 33 degrees and split it into 15 and 18. (33-15=18). Since you know that the 15 degrees has a 2.5 magnitude you can now compose the 33 degree angle as a 15 degree vector with a magnitude of 2.5 and a 18 degree vector of unknown "W" magnitude. Now you know that the "W" vector has a j value( <i,j> component form) of 2.5. So Cos(18)=2.5/W. Then solve for W, which turns out to be about 2.63 magnitude. Plug that back into the component form and you get <cos(33)*2.63, sin(33)*2.63> which turns out to be <2.20,1.43>.

4. butterflyprincess

Cool thanks but like I am a little confused on how you got to this part.. "<cos(33)*2.63, sin(33)*2.63>"

5. butterflyprincess

you there?

6. hba

Yeah

7. hba

Cos(18)=2.5/w > Solve for w,You get 2.63.

8. hba

Now we just have to plug it in component form :)

9. butterflyprincess

ohhhh ok thanks! :DD