Given that y=(sin4x)(sec3x), use the product rule to find dy/dx

First, recall the Product rule: f(x)=g(x)*h(x), f'(x)=h(x)*g'(x)+h'(x)*g(x)This reveals the next step, to find the derivatives of our two subsidiary functions(g and h) d/dx * (sin4x) = 4cos(4x) , and d/dx (sec3x)= 3sec(3x)tan(3x) , this one comes from the list of trigonometric identities Now the answer is simple to find by plugging in the values which we have found to our equation. dy/dx= sec3x4cos4x+3sec(3x)tan(3x)*sin4xThis is the answer as required.

EF
Answered by Edward F. Maths tutor

3807 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

how do integrate an equation with a surd or a fraction?


Line AB has equation 4x+5y+2=0. If the point P=(p, p+5) lies on AB, find P . The point A has coordinates (1, 2). The point C(5, k) is such that AC is perpendicular to AB. Find the value of k.


Finding stationary points


a typical question would be a setof parametric equations y(t) and x(t), asking you to find dy/dx and then the tangent/normal to the curve at a certain point (ie t = 2)


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