Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °

You are not logged in.

- Topics: Active | Unanswered

**Arman Ansary****Member**- Registered: 2017-10-07
- Posts: 4

This was in my book:

The remainder when x^45 is divided by x^2 - 1 is :-

a)2x

b)-x

c)0

d)x

e)None of these

THIS WAS UNDER THE LEVEL 1 QUESTION SECTION.

Try to answer and it would be good if you show the method.

Offline

**bob bundy****Administrator**- Registered: 2010-06-20
- Posts: 8,382

hi Arman Ansary

Welcome to the forum.

Start by writing

where Q is the quotient and R the remainder, both functions of x.

R must be a linear function (ax + b) because if it had higher power of x, you would be able to further divide it by x^2 -1

If you put x=1 you will get one equation with a and b; and putting x = -1 will give another. Together you can solve for a and b.

Hope that helps,

Bob

Children are not defined by school ...........The Fonz

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

Offline

**iamaditya****Member**- From: Planet Mars
- Registered: 2016-11-15
- Posts: 766

Its easy.

Don't you think it should be in *Help Me*.

Practice makes a man perfect.

There is no substitute to hard work

All of us do not have equal talents but everybody has equal oppurtunities to build their talents.-APJ Abdul Kalam

Offline

**bob bundy****Administrator**- Registered: 2010-06-20
- Posts: 8,382

Yes but I'm just being helpful anyway.

Bob

Children are not defined by school ...........The Fonz

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

Offline