Hi Samuel,
That depends on how “product cost” is saved on your site.
If you mean that you set this “product cost” as standard WooCommerce price, then you need to set Formula to:
[math_ceil]x*2[/math_ceil]-0.01+2
And if you mean that you are using some additional plugin to set this “product cost”, then you need to know product meta key in which cost is stored in product. For example, if you are using our Cost of Goods for WooCommerce plugin, then cost will be saved in _alg_wc_cog_cost
meta key, so you need to set Formula to:
[math_ceil][product_meta key="_alg_wc_cog_cost"]*2[/math_ceil]-0.01+2
Hope that helps. Please let me know if something is not working as expected or if you have any questions. And if you like the plugin, please consider leaving us a rating.