Indifference curve and its shape

An indifference curve is a graphical representation of the different combinations of two goods that yield the same level of satisfaction for a consumer. The shape of the indifference curve depends on the preferences of the consumer.

Convex to the origin

If a consumer's preferences for the two goods are such that they prefer a combination of both goods, their indifference curve will be convex to the origin. This is because as the consumer moves along the curve, they are willing to give up more of one good to obtain more of the other good, but at an increasingly diminishing rate.

Example

For example, if a consumer likes both pizza and burgers, their indifference curve will be convex to the origin. As the consumer moves along the curve, they are willing to give up more pizza to obtain more burgers, but at an increasingly diminishing rate.

Why not concave or L-shaped?

A concave indifference curve would imply that the consumer is willing to give up more of one good for a small increase in the other good. This is not consistent with rational consumer behavior.

An L-shaped indifference curve would imply that the consumer is indifferent between all combinations of one good and a certain quantity of the other good. This is unrealistic because most consumers have preferences for both goods.

Conclusion

Therefore, a convex indifference curve is the most common and realistic shape, as it reflects a consumer's willingness to trade off between the two goods in a diminishing manner.

It is because diminishing MRS or slope of IC. in order to gain an additional unit of good 1 the consumer is prepared to give up less and less units of good 2 . this cause diminishing MRS and accordingly convex IC.