If A=<2,2> and B=<9,4>, what is ||A+B||||A||||B||?

1 Answer
Mar 19, 2016

||A+B||||AB||=85125

Explanation:

A+B=C
Cx=Ax+Bx=2+9=7
Cy=Ay+By=2+4=6
||C||=C2x+C2y ||C||=72+62=49+36
||C||=85

AB=D
Dx=AxBx=29=11
Dy=AyBy=24=2
||D||=Dx2+Dy2 ||D||=(11)2+(2)2
||D||=121+4 ||D||=125
||A+B||||AB||=||C||||D||
||A+B||||AB||=85125