What is the coefficient of x^2 in the expansion of (5+2x)^0.5?

  1. We the answer in question in the form A(1+B)0.5 and we can do that by factorising out the 5. This gives 50.5(1+0.4x)0.5. 2. Identify the formula we are going to use and put in the numbers from this equation to get 50.5(1 + 0.50.4x + (0.5-0.50.4/2!)(0.4)2x2 + ... 3. At this point we have the x2 term so no further working is needed other than to multiply out the coeffiicient in front of the term to give -0.0250.5 = - 0.0447 (to 3SF)
AA

Related Maths A Level answers

All answers ▸

Integrate the function f(x) = ax^2 + bx + c over the interval [0,1], where a, b and c are constants.


The point P (4, –1) lies on the curve C with equation y = f( x ), x > 0, and f '(x) =x/2 - 6/√x + 3. Find the equation of the tangent to C at the point P , giving your answer in the form y = mx + c. Find f(x)


What is exactly differentiation?


Find the derivative and following function and hence find the value of coordinates for when the function is at a stationary point: