The side of a square isacm long, and is increasing at the rate ofbcm per hour. How fast is the area increasing?
Open in App
Solution
Answer:
Length of side of square = a cm
And increment in sides per hr = b cm
We know area of square = ( Side length )2
So,
Area of square = a2
After one hr = ( a + b ) 2 = a2 + b2 + 2ab
Then
Area is increase by = a2 + b2 + 2ab - a2 = b2 + 2ab​ ( Ans )