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This position requires an advanced technique called forcing chains.

This technique involves looking at cells which have two candidates and tracing out the implications of each alternative. If they both lead to the same result (for example, eliminating the same candidate from some cell), then you can rest assured that that result is correct.

It is helpful when tracing out the implications of each alternative to use different colored pens or pencils. When drawing out the implications, you may also want to reproduce the candidates below themselves in different colors, so that you don't confuse your exploration of possibilities with permanent inferences.

Here is an example of using this technique on your grid:

This technique is based on a general pattern of reasoning called Separation of Cases, which can be represented schematically as:

φ or ψ
φ → χ
ψ → χ
Thus, χ

This position requires an advanced technique called forcing chains.

This technique involves looking at cells which have two candidates and tracing out the implications of each alternative. If they both lead to the same result (for example, eliminating the same candidate from some cell), then you can rest assured that that result is correct.

It is helpful when tracing out the implications of each alternative to use different colored pens or pencils. When drawing out the implications, you may also want to reproduce the candidates below themselves in different colors, so that you don't confuse your exploration of possibilities with permanent inferences.

Here is an example of using this technique on your grid:

This technique is based on a general pattern of reasoning which can be represented schematically as:

φ or ψ
φ → χ
ψ → χ
Thus, χ

This position requires an advanced technique called forcing chains.

This technique involves looking at cells which have two candidates and tracing out the implications of each alternative. If they both lead to the same result (for example, eliminating the same candidate from some cell), then you can rest assured that that result is correct.

It is helpful when tracing out the implications of each alternative to use different colored pens or pencils. When drawing out the implications, you may also want to reproduce the candidates below themselves in different colors, so that you don't confuse your exploration of possibilities with permanent inferences.

Here is an example of using this technique on your grid:

This technique is based on a general pattern of reasoning called Separation of Cases, which can be represented schematically as:

φ or ψ
φ → χ
ψ → χ
Thus, χ

This position requires an advanced technique called forcing chains.

This technique involves looking at cells which have two candidates and tracing out the implications of each alternative. If they both lead to the same result (for example, eliminating the same candidate from some cell), then you can rest assured that that result is correct.

It is helpful when tracing out the implications of each alternative to use different colored pens or pencils. When drawing out the implications, you may also want to reproduce the candidates below themselves in different colors, so that you don't confuse your exploration of possibilities with permanent inferences.

Here is an example of using this technique on your grid:

This technique is based on a general pattern of reasoning called Separation of Cases, which can be represented schematically as:

φ or ψ
φ → χ
ψ → χ
Thus, χ

This position requires an advanced technique called forcing chains.

This technique involves looking at cells which have two candidates and tracing out the implications of each alternative. If they both lead to the same result (for example, eliminating the same candidate from some cell), then you can be assured that that result is correct.

It is helpful when tracing out the implications of each alternative to use different colored pens or pencils. When drawing out the implications, you may also want to reproduce the candidates below themselves in different colors, so that you don't confuse your exploration of possibilities with actual cancellations.

Here is an example of using this technique on your grid:

This technique is based on a general pattern of reasoning called Separation of Cases, which can be represented schematically as:

φ or ψ
φ → χ
ψ → χ
Thus, χ

This position requires an advanced technique called forcing chains.

This technique involves looking at cells which have two candidates and tracing out the implications of each alternative. If they both lead to the same result (for example, eliminating the same candidate from some cell), then you can rest assured that that result is correct.

It is helpful when tracing out the implications of each alternative to use different colored pens or pencils. When drawing out the implications, you may also want to reproduce the candidates below themselves in different colors, so that you don't confuse your exploration of possibilities with permanent inferences.

Here is an example of using this technique on your grid:

This technique is based on a general pattern of reasoning called Separation of Cases, which can be represented schematically as:

φ or ψ
φ → χ
ψ → χ
Thus, χ