In-Law 
A dream about an in-law represents scrutiny and insecurity in regards to new responsibilities. You may have recently experienced a promotion but be having conflict with your boss. This person has strong influence upon your life and you may feel the problems someone is causing you for an unexpected downside of a greater reward.
Alternatively, to dream of your in-law symbolizes an evolving working relationship. The dream may also be a hint to strictly adhere to the rules and be mindful of your actions.
Mathematics
To dream about mathematics suggests that you are attempting to assess an issue and discover the best way to resolve it. You should use practical and sensible reasoning rather than your instincts and feelings.
To dream that you are unable to solve a mathematical problem or equation is a reflection of an issue that you are unsure about. This dream may be leading you towards a resolution.
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