Show that sqrt(27) + sqrt(192) = a*sqrt(b), where a and b are prime numbers to be determined

We want to get the the sqrt(27) and sqrt(192) so that they have the same number in the square so they can then be added together. We will look at the factorisation of 27, 192. We can see 27 is divisible by 3, 3x9, so we can say sqrt(27) = sqrt(3) * sqrt(9) as the sqrt(9) is 3, we can write sqrt(27) = 3* sqrt(3). Now we look at 192 and we want it to be in the form asqrt(3) so we look divide 192 by 3 to get 64. So we know sqrt(192) = sqrt(64)sqrt(3) as sqrt(64) = 8 we can write sqrt(64) as 8. Hence we have sqrt(192) = 8sqrt(3) so sqrt(192) + sqrt(27) = 8sqrt(3) + 3sqrt(3) = 11sqrt(3). Hence a,b equal 11,3 respectively and we can see that a,b are both prime.

Answered by Luke H. Maths tutor

2842 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

Integrate cos(4x)+16x^3 with respect to x


a) Find the indefinite integral of sec^2(3x) with respect to x. b) Using integration by parts, or otherwise, find the indefinite integral of x*sec^2(3x) with respect to x.


How do I do definite integrals?


Differentiate arctan(x) with respect to x. Leave your answer in terms of x


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