# What does it mean by 'intensive form'?

I encountered this phrase while reading up on growth models - that is to work with a function in intensive form. What does it mean when a function is in intensive form?

Thanks!

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– BKay
Aug 12 '15 at 18:52

The intensive form of the production function is derived from the following. Let us assume a production function, F, with inputs of capital, K, and labor and technology, AL. Thus, output, $Y = F(K,AL)$. Assuming constant returns to scale, i.e. $F(cK,cAL) = cF(K,AL)$, we can say $F(K,AL) = ALF(K/AL, 1)$. The intensive form of the production function, f, takes the argument k = K/AL. k is ratio of capital to labour, or how much capital is there per effective unit of labour. $f(k) = Y/AL = F(K/AL, 1)$, or the output per effective unit of labour.