proof for the derivative of sin(x) is cos(x) (5 marks)

let f(x)=sin x f'(x) lim h-> 0 = ( sin(x+h) - sin(x))/h. f'(x) lim h-> 0 =( sin(x)cos(h) + cos(x)sin(h) - sin(x))/ h. f'(x) lim h-> 0=(sin(x)(cos(h)-1)/h + cos(x) (sin(h))/h. then as h tends to zero. (cos(h)-1)/h=0 and sin(h)/h =1. f'(x)= cos(x) QED

Answered by Nicola P. Maths tutor

3361 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

how to derive escape velocity


How do you find the point or points of intersection of a straight line and a circle?


The point on the circle x^2+y^2+6x+8y = 75 which is closest to the origin, is at what distance from the origin? (Taken from an MAT paper)


A curve has the equation x^2 +2x(y)^2 + y =4 . Find the expression dy/dx in terms of x and y [6]


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences