What is the Equation for the Scalar and Vector Products of Two Vectors?

[0517]

what can be defined by the following equation?
im new to calculus, and I'm totally lost now :(

 

[tiny-tim]

welcome to pf!

hi janice! welcome to pf!

(try using | on your keyboard and the X² icon just above the Reply box )

hint: if the angle between vectors a and b is θ, what does the equation say?

 

[I like Serena]

what can be defined by the following equation?
im new to calculus, and I'm totally lost now :(

I guess you need to know that:
1. (a, b) = |a| |b| cos phi
2. |a x b| = |a| |b| sin phi

 

[0517]

hi janice! welcome to pf!

(try using | on your keyboard and the X² icon just above the Reply box )

hint: if the angle between vectors a and b is θ, what does the equation say?

urgh, good question.
i didn't know how to answer, i think I'm super blur in this topic :(

 

[0517]

hi janice! welcome to pf!

(try using | on your keyboard and the X² icon just above the Reply box )

hint: if the angle between vectors a and b is θ, what does the equation say?

urgh, good question.
i didn't know how to answer, i think I'm super blur in this topic :(

a · b = |a| |b| cos θ

so the square of it = ? @@

 

[tiny-tim]

so the square of it = ? @@

|a|² |b|² cos²θ

and the square of the second part is … ? ​