Rewrite the expression as a sum or difference, then simplify if possible.

the expression    as a sum or difference is   and , is simplified as   .

Step-by-step explanation:

We need to rewrite the expression as a sum or difference , them simplify if possible  , And the expression is :

From trigonometric identity we know that

Using the above identity we get:

⇒  

⇒  

⇒  

⇒  

⇒  

Therefore , the expression    as a sum or difference is   and , is simplified as   .

44

step-by-step explanation:

the

7.9m and 4.3°

step-by-step explanation:

let east be +x and north be +y, x = distance * cos θ, y = distance * sin θ  

for 3.5 south, y = -3.5  

for 8.2, x = 8.2 * cos 30 and y = 8.2 * sin 30  

for 15 west, x = -15  

total x = 8.2 * cos 30 – 15 ≈ -7.9  

total y = -3.5 + 8.2 * sin 30 = 0.6  

magnitude = [(8.2 * cos 30 – 15)^2 + 0.6^2)]^0.5  

the magnitude is approximately 7.9 m  

tan θ = y/x = 0.6/-7.9  

the angle is approximately 4.3˚ north of west