Answer:
D) 9 postcards with 2 shells each.
Explanation:
9 x 2 = 18
Therefore, 9 postcards with 2 shells each is the correct answer.
Please give brainliest.
Because

therefore
f(x) = (x-3)(2x² + 10x - 1) + k, where k = constant.
Because f(3) = 4, therefore k =4.
The polynomial is
f(x) = 2x³ + 10x² - x - 6x² - 30x + 3 + 4
= 2x³ + 4x² - 31x + 7
Answer: f(x) = 2x³ + 4x² - 31x + 7
We know that: <span>3(x-1)^2-162=0
or (x-1)</span>²= 162:3
and (x-1)²= 54
we <span>take the square root of both sides
* x-1=</span>√54= 3√6 or x=1+3√6
* x-1= -<span>√54= -3√6 or x=1-3√6
This equation has 2 solutions</span>
Answer:
2a(7b+5)
Step-by-step explanation:
yeah-ya....... right?
The question is:
Check whether the function:
y = [cos(2x)]/x
is a solution of
xy' + y = -2sin(2x)
with the initial condition y(π/4) = 0
Answer:
To check if the function y = [cos(2x)]/x is a solution of the differential equation xy' + y = -2sin(2x), we need to substitute the value of y and the value of the derivative of y on the left hand side of the differential equation and see if we obtain the right hand side of the equation.
Let us do that.
y = [cos(2x)]/x
y' = (-1/x²) [cos(2x)] - (2/x) [sin(2x)]
Now,
xy' + y = x{(-1/x²) [cos(2x)] - (2/x) [sin(2x)]} + ([cos(2x)]/x
= (-1/x)cos(2x) - 2sin(2x) + (1/x)cos(2x)
= -2sin(2x)
Which is the right hand side of the differential equation.
Hence, y is a solution to the differential equation.