What is the value of 5xy if X^2 10y^2 1 is smaller than equal to 2y (3...
Explanation of the problem
The problem states that we need to find the value of 5xy given that X^2 + 10y^2 + 1 is smaller than or equal to 2y(3x-1). We need to solve this inequality to determine the range of values that x and y can take and then use those values to find the value of 5xy.
Solving the inequality
To solve the inequality, we first simplify the expression on the right-hand side:
Now we can rewrite the inequality as:
- X^2 + 10y^2 + 1 <= 6xy="" -="">=>
Next, we move all the terms to one side:
- X^2 - 6xy + 10y^2 - 2y + 1 <=>=>
We can factor the quadratic expression to get:
Now we need to determine the range of values for x and y that satisfy this inequality. We can do this by considering the signs of each factor:
- If both factors are positive or both are negative, the inequality is not satisfied.
- If one factor is zero, the inequality is satisfied. This occurs when x = 2y-1 or x = 5y-1.
- If x-2y+1 is negative and x-5y+1 is positive, the inequality is satisfied. This occurs when x < 2y-1="" and="" x="" /> 5y-1.
- If x-2y+1 is positive and x-5y+1 is negative, the inequality is satisfied. This occurs when 2y-1 < x="" />< />
Finding the value of 5xy
Now that we have determined the range of values for x and y that satisfy the inequality, we can find the value of 5xy by substituting the values of x and y into the expression:
- When x = 2y-1, 5xy = 5(2y-1)y = 10y^2 - 5y
- When x = 5y-1, 5xy = 5(5y-1)y = 25y^2 - 5y
We can see that as y increases, the value of 5xy increases as well. Therefore, the maximum value of 5xy occurs when y is at its maximum value, which is when y = 1/10. Substituting this value into the expression for x, we get:
- When x = 2(1/10)-1 = -8/10, 5xy = 10(1/10)^2 - 5(1/10) = 1/2 - 1/