p.q is certainly not equal to 9.CheesyPeeps said:Homework Statement
Homework Equations
p.q+p.r
The Attempt at a Solution
I've expanded p.(q+r) to give p.q+p.r. The magnitude of p is 3, and since ABE is an equilateral triangle, the magnitude of q is also 3, right? So then p.q=9, but the answer scheme states that p.q=4.5.
I'm still pretty new to mathematics, so I'm probably missing something really obvious, but it's better to make the mistakes now than in my exam!
y_A said:
Expanding p.(q+r) is a mathematical expression that involves the use of parentheses to group numbers or variables and perform operations on them. In this case, p, q, and r are variables that represent numbers or other mathematical expressions.
To expand p.(q+r), you need to use the distributive property, which states that a(b+c) = ab + ac. In this case, p is being multiplied by the sum of q and r, so we can expand it as p.q + p.r.
Expanding p.(q+r) helps us simplify mathematical expressions by breaking them down into smaller, more manageable parts. This can make it easier to solve equations or manipulate expressions to find their solutions.
Sure, let's say we have the expression p.(2+3). Using the distributive property, we can expand it as p.2 + p.3, which simplifies to 2p + 3p. Similarly, if we have p.(x+y), we can expand it as p.x + p.y.
Yes, there are other methods such as the FOIL method, which is commonly used to expand expressions with two sets of parentheses. However, the distributive property is the most straightforward and commonly used method for expanding p.(q+r) or similar expressions.