Question

If vectors l P l , l Q l and l R l have magnitudo 5, 12, 13 units and l P l+l Q l= l R l, the angle between l Q l and l R l is
a. cos^-1 5/12
b. cos^-1 5/13
c. cos^-1 12/13
d. cos^-1 7/13 ​

Answer 1

Answer:

"Many people in California figured gold was there, but it was James W. Marshall on January 24, 1848, who saw something shiny in Sutter Creek near Coloma, California. He had discovered gold unexpectedly while overseeing construction of a sawmill on the American River."

Answer 2

"cos

−1

13

12

∣

P

∣=5,∣

Q

∣=12 and ∣

R

∣=13

cosθ=

R

Q

=

13

12

∴θ=cos

−1

(

13

12

)"