Is my approach at deriving $\sum_{k=1}^{m} n_{k} log (p_{k}) + \lambda (1 - \sum_{k=1}^{m} p_k)$ correct?

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Given the sum:

$\sum_{k=1}^{m} n_{k} log (p_{k}) + \lambda (1 - \sum_{k=1}^{m}p_k)$ ?

derive for p and $\lambda$, So far I've gotten it to this, but I'm unsure if my answers are correct, could someone clarify?

Assume $log(x)$ to base $e$

$f(p) = \sum_{k=1}^{m} n_{k} log (p_{k}) + \lambda - \lambda\sum_{k=1}^{m}p_k$

$=>\lambda + \sum_{k=1}^{m} n_{k} log (p_{k}) - \lambda\sum_{k=1}^{m}p_k$

$=> \lambda + \sum_{k=1}^{m} \frac{n_{k}}{p_k ln(e)} - \lambda\sum_{k=1}^{m}0$

$f'(p) = \lambda + \sum_{k=1}^{m} \frac{n_{k}}{p_k}$

is this correct?

$f(\lambda) = \lambda +\sum_{k=1}^{m} n_{k} log p_{k} - \lambda\sum_{k=1}^{m}p_k$

$f'(\lambda) = \lambda +\sum_{k=1}^{m} n_{k} log p_{k} - \lambda\sum_{k=1}^{m}p_k$

$=> 0 + \sum_{k=1}^{m} n_{k} log p_{k} - 0\sum_{k=1}^{m}p_k$

$f'(\lambda) = \sum_{k=1}^{m} n_{k} log p_{k}$

Could anyone clarify if these are correct or am I very off the mark? Any and all help wold be greatly appreciated