A-Level Maths OCR B (MEI) H640

9: Calculus

#9.1

Know and use that the gradient of a curve at a point is given by the gradient of the tangent at the point.

#9.10

Be able to differentiate ekxe^{kx}, akxa^{kx} and lnx\ln{x}.

Including related sums, differences and constant multiples.

#9.11

Be able to differentiate the trigonometrical functions: sinkx\sin{kx}; coskx\cos{kx}; tankx\tan{kx} for xx in radians.

Including their constant multiples, sums and differences. Differentiation from first principles for sinx\sin{x} and cosx\cos{x}.

#9.12

Be able to differentiate the product of two functions.

*The product rule: y=uvy = uv,

dydx=udvdx+vdudx\dfrac{dy}{dx} = u\dfrac{dv}{dx} + v\dfrac{du}{dx}

Or [f(x)g(x)]=f(x)g(x)+f(x)g(x)[f(x)g(x)]' = f(x)g'(x) + f'(x)g(x) *

#9.13

Be able to differentiate the quotient of two functions.

*The quotient rule: y=udvy = \dfrac{u}{dv},

dydx=vdudxudvdxv2\dfrac{dy}{dx} = \dfrac{v\dfrac{du}{dx} - u\dfrac{dv}{dx}} {v^2}

[f(x)g(x)]=f(x)g(x)f(x)g(x)(g(x))2\Bigg[\dfrac{f(x)}{g(x)}\Bigg]' = \dfrac{f'(x)g(x) - f(x)g'(x)}{\big(g(x)\big)^2} *

#9.14

Be able to differentiate composite functions using the chain rule.

iy=f(u)y=f(u), u=g(x)u=g(x),

dydx=dydu×dudx\dfrac{dy}{dx} = \dfrac{dy}{du} × \dfrac{du}{dx}

Or {f[g(x)]}=f[g(x)]g(x)\big\{f\big[g(x)\big]\big\}' = f'\big[g(x)\big]g'(x)

#9.15

Be able to find rates of change using the chain rule, including connected rates of change and differentiation of inverse functions.

dydx=1(dydx)\dfrac{dy}{dx} = \dfrac{1}{\Big(\dfrac{dy}{dx}\Big)}

#9.16

Be able to differentiate a function or relation defined implicitly.

*e.g. (x+y)2=2x(x + y)^2 = 2x.

Excludes: Second and higher derivatives.*

#9.17

Understand that a section of curve which has increasing gradient (and so positive second derivative) is concave upwards. Understand that a section of curve which has decreasing gradient (and so negative second derivative) is concave downwards.

*\huge\smallsmile concave upwards (convex downwards) \huge\smallfrown concave downwards (convex upwards)

Notation: The wording “concave upwards” or “concave downwards” will be used in examination questions.*

#9.18

Understand that a point of inflection on a curve is where the curve changes from concave upwards to concave downwards (or vice versa) and hence that the second derivative at a point of inflection is zero. Be able to use differentiation to find stationary and non-stationary points of inflection.

Learners are expected to be able to find and classify points of inflection as stationary or non-stationary. Distinguish between maxima, minima and stationary points of inflection.

#9.19

Know that integration is the reverse of differentiation.

Fundamental Theorem of Calculus.

#9.2

Know and use that the gradient of the tangent at a point A on a curve is given by the limit of the gradient of chord AP as P approaches A along the curve.

Excludes: The modulus function.

#9.20

Be able to integrate functions of the form kxnkx^n where kk is a constant and n1n \neq -1.

Including related sums and differences.

#9.21

Be able to find a constant of integration given relevant information.

e.g. Find yy as a function of xx given that dydx=x2+2\dfrac{dy}{dx} = x^2 + 2and y=7y = 7 when x=1x = 1.

#9.22

Know what is meant by indefinite and definite integrals. Be able to evaluate definite integrals.

e.g. 13(3x2+5x1) dx\displaystyle\int_1^3{(3x^2 + 5x - 1)}~dx.

#9.23

Be able to use integration to find the area between a graph and the x-axis.

*Includes areas of regions partly above and partly below the x-axis. General understanding that the area under a graph can be found as the limit of a sum of areas of rectangles.

Excludes: Formal understanding of the continuity conditions required for the Fundamental Theorem of Calculus.*

#9.24

Be able to integrate ekxe^{kx}, 1x\dfrac{1}{x}, sinkx\sin{kx}, coskx\cos{kx} and related sums, differences and constant multiples.

*1x dx=lnx+c,x0\displaystyle\int{\dfrac{1}{x}}~dx = \ln{|x|} + c, x \neq 0 xx in radians for trigonometrical integrals.

Excludes: Integrals involving inverse trigonometrical functions.*

#9.25

Understand integration as the limit of a sum.

Know that limδx0abf(x)δx=abf(x)dx\lim\limits_{\delta x→0} \displaystyle\sum_a^b f(x) \delta x = \displaystyle\int_a^b{f(x)} dx

#9.26

Be able to use integration to find the area between two curves.

Learners should also be able to find the area between a curve and the yy-axis, including integrating with respect to yy.

#9.27

Be able to use integration by substitution in cases where the process is the reverse of the chain rule (including finding a suitable substitution).

e.g. (1+2x)8(1+2x)^8, x(1+x2)8x(1+x^2)^8, xex2xe^{x^2}, 12x+3\dfrac{1}{2x+3} Learners can recognise the integral, they need not show all the working for the substitution.

#9.28

Be able to use integration by substitution in other cases.

*Learners will be expected to find a suitable substitution in simple cases e.g. x(x+1)3\dfrac{x}{(x+1)^3}.

Excludes: Integrals requiring more than one substitution before they can be integrated.*

#9.29

Be able to use the method of integration by parts in simple cases.

*Includes cases where the process is the reverse of the product rule, e.g. xexxe^x. More than one application of the method may be required. Includes being able to apply integration by parts to lnx\ln{x}.

Excludes: Reduction formulae.*

#9.3

Understand and use the derivative of f(x)f(x) as the gradient of the tangent to the graph of y=f(x)y = f(x) at a general point (x,y)(x, y). Know that the gradient function dydx\dfrac{dy}{dx} gives the gradient of the curve and measures the rate of change of yy with respect to xx.

*Be able to deduce the units of rate of change for graphs modelling real situations. The term derivative of a function.

Notation: dydx=limδx0δyδx\dfrac{dy}{dx} = \lim\limits_{δx→0} \dfrac{δy}{δx}f(x)=limh0(f(x+h)f(x)h)f'(x) = \lim\limits_{h→0} \Bigg(\dfrac{f(x+h) - f(x)}{h} \Bigg)*

#9.30

Be able to integrate using partial fractions that are linear in the denominator.

#9.31

Be able to formulate first order differential equations using information about rates of change.

Contexts may include kinematics, population growth and modelling the relationship between price and demand.

#9.32

Be able to find general or particular solutions of first order differential equations analytically by separating variables.

Equations may need to be factorised using a common factor before variables can be separated.

#9.33

Be able to interpret the solution of a differential equation in the context of solving a problem, including identifying limitations of the solution.

Includes links to kinematics.

#9.4

Be able to sketch the gradient function for a given curve.

#9.5

Be able to differentiate y=kxny = kx^n where kk is a constant and nn is rational, including related sums and differences.

Differentiation from first principles for small positive integer powers.

#9.6

Understand and use the second derivative as the rate of change of gradient.

Notation: f(x)=d2ydx2f''(x) = \dfrac{d^2y}{dx^2}

#9.7

Be able to use differentiation to find stationary points on a curve: maxima and minima.

Distinguish between maximum and minimum turning points.

#9.8

Understand the terms increasing function and decreasing function and be able to find where the function is increasing or decreasing.

In relation to the sign of dydx\dfrac{dy}{dx}.

#9.9

Be able to find the equation of the tangent and normal at a point on a curve.

8
Exponentials and logarithms
10
Numerical methods