Q3 of 21 Page 75

Prove that Use this to compute correct to two decimal places.

(√2 + 1) (√2 – 1) = (√2)2 – (1)2 [∵ (a+b)(a-b) = a2-b2]


⇒ (√2 + 1) (√2 – 1) = 2 – 1


⇒ (√2 + 1) (√2 – 1) = 1


Hence, (√2 + 1) (√2 – 1) = 1


Now,







More from this chapter

All 21 →
1

Calculate the length of the sides of the equilateral triangle on the right, correct to a millimetre.

 2

The picture shows the vertices of a regular hexagon connected by lines.


i) Prove that the inner red hexagon is also regular.


ii) How much of a side of the large hexagon is a side of the small hexagon?


iii) How much of the area of the large hexagon is the area of the small hexagon?

 4

Compute correct to two decimal places.

 5

Prove that Can you find other numbers like this?