<span>let y = sec^2 ( pi x )
y' = 2 sec ( pi x ) sec( pi x ) tan ( pi x ) pi
y' = 2pi sec^2 ( pi x ) tan ( pi x )
y''= 2pi sec^2 ( pi x ) * sec^2 ( pi x ) * pi + 2pi tan ( pi x ) * 2pi sec^2 ( pi x ) tan ( pi x )
y'' = 2 pi^2 sec^4 ( pi x ) + 4 pi^2 sec^2 ( pi x ) tan^2 ( pi x )</span>
Answer: A coefficient refers to a number or quantity placed with a variable
Step-by-step explanation: For example, in the expression 3x, 3 is the coefficient but in the expression x2 + 3, 1 is the coefficient of x2. In other words, a coefficient is a multiplicative factor in the terms of a polynomial, a series, or any expression.
To solve this problem you must apply the proccedure shown below:
1. The formula for calculate the perimeter of a rectangle is:
Where 
is the length and 
is the width.
2. The length is 
more than the width, therefore:
3. Substitute values into the formula for calculate the perimeter and solve for the width:
3. Then, the length is:
The answer is: The length is 
and the width is 
