CameraIcon

SearchIcon

MyQuestionIcon

1

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Expansion of (a+b)^3

The sum of tw...

Question

The sum of two numbers is 9 and their product is 20. Find the sum of their cubes.

A

189

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

B

1269

No worries! We‘ve got your back. Try BYJU‘S free classes today!

C

190

No worries! We‘ve got your back. Try BYJU‘S free classes today!

D

79

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is A 189
Given sum of two numbers is 9 and their product is 20.

Let the numbers be a and b.

a + b = 9

ab = 20

Cubing on both sides gives
(a + b)3 = 93
a³+ b³+ 3ab(a + b) = 729
a³+ b³+ 60(9) = 729
a³+ b³= 729 - 540 = 189
a³+ b³= 729 - 540 = 189

Suggest Corrections

thumbs-up

5

Similar questions

Q. Sum of two numbers is 10 and their product is 24. Find the sum of their cubes.

Q. The sum of two numbers is

9

and their product is

20

. Find sum of their squares.

Q. If the sum of three numbers be 9 the sum of their squares be 29 and their sum of cubes be 99 then find the product

Q. If sum of three numbers is

4

, sum of their squares is

14

, sum of their cubes is

34

and their products is

- 6

, then sum of products of two numbers at a time is

Q. The sum of two numbers is 7 and the sum of their cubes is 133, find the sum of their squares.

Join BYJU'S Learning Program

similar_icon

Related Videos

lock

Expansion of (a+b)^3

MATHEMATICS

Watch in App

explore_more_icon

Explore more

Expansion of (a+b)^3

Standard VIII Mathematics

Join BYJU'S Learning Program

CrossIcon