Question

a cube of side 4 cm is painted on all of its faces if it is sliced into one cubic centimetre cube then number of 1 cubic centimetre cubes will have exactly their three faces painted is(a) 32 cubes (b) 22 cubes (c) 15 cubes (d) 8 cubes plzzzzzzzzzzzzzzzz answer me​

Answer 1

Answer:

8

Step-by-step explanation:

This doesn't depend of measurements. It depends only on the parts which are painted from 3 sides. There are no possible way for a peice taken from only one side or 2 side. You must search for such parts which were having their atleast faces in outward direction in the original cube. As cubes have only 8 edges, there are only 8 such places(cubes formed when we cut their edges).

Those edges(the sharp edge, not meant for sides) have their edges in 3 directions(outwards), which would have got painted.

On this basis, we can say that option (d) is correct

Answer 2

Step-by-step explanation:

Aakash test ke Questions yaha mat pucho..........

Question : Prove that√5 is irrational.

Answer :

Let us assume that √5 is a rational number.

Sp it t can be expressed in the form p/q where p,q are co-prime integers and q≠0

⇒√5=p/q

On squaring both the sides we get,

⇒5=p²/q²

⇒5q²=p² —————–(i)

p²/5= q²

So 5 divides p

p is a multiple of 5

⇒p=5m

⇒p²=25m² ————-(ii)

From equations (i) and (ii), we get,

5q²=25m²

⇒q²=5m²

⇒q² is a multiple of 5

⇒q is a multiple of 5

Hence, p,q have a common factor 5. This contradicts our assumption that they are co-primes. Therefore, p/q is not a rational number

√5 is an irrational number

Hence proved