laborious ... enclosed may help ... cos -angle = cos +plus angle ... sin - anfle = - sine angle
cos is even function, sine is odd ... draw rhe graohs
Answer:
Stretch can be obtained using the Elastic potential energy formula.
The expression to find the stretch (x) is 
Explanation:
Given:
Elastic potential energy (EPE) of the spring mass system and the spring constant (k) are given.
To find: Elongation in the spring (x).
We can find the elongation or stretch of the spring using the formula for Elastic Potential Energy (EPE).
The formula to find EPE is given as:

Rewriting the above expression in terms of 'x', we get:

Example:
If EPE = 100 J and spring constant, k = 2 N/m.
Elongation or stretch is given as:

Therefore, the stretch in the spring is 10 m.
So, stretch in the spring can be calculated using the formula for Elastic Potential Energy.
No. Quatro cientos grads.
<h3>right --- 20 + 10 = 30 N</h3>
<h3>left --- 10 N</h3>
<h3>resultant force --- 30 - 10 = 20 N</h3>
<h2>B. 20 N to the left</h2>
Explanation:
Formula to calculate the electric potential is as follows.

Putting the given values into the above formula as follows.

= ![\frac{9 \times 10^{9}}{0.25}[\frac{-3.3}{\sqrt{2}} + 4.2] \times 10^{-6}](https://tex.z-dn.net/?f=%5Cfrac%7B9%20%5Ctimes%2010%5E%7B9%7D%7D%7B0.25%7D%5B%5Cfrac%7B-3.3%7D%7B%5Csqrt%7B2%7D%7D%20%2B%204.2%5D%20%5Ctimes%2010%5E%7B-6%7D)
= 
Hence, electric potential at point A is
.
Now, the electric potential at point B is as follows.

= ![\frac{9 \times 10^{9}}{0.25} [-3.3 + \frac{4.2}{\sqrt{2}}] \times 10^{-6}](https://tex.z-dn.net/?f=%5Cfrac%7B9%20%5Ctimes%2010%5E%7B9%7D%7D%7B0.25%7D%20%5B-3.3%20%2B%20%5Cfrac%7B4.2%7D%7B%5Csqrt%7B2%7D%7D%5D%20%5Ctimes%2010%5E%7B-6%7D)
= 
Hence, electric potential at point B is
.