7.4 A A*B=0

• Wiskunde
• Middelbare school
• havo
• Leerjaar 2

Invoegen plattegrond op niveau

Invoegen plattegrond op niveau

Today

You are able to solve equations written in the form A x B = 0.

Tell your neighbour an example of a multiplication with result 0.

Conclusion

When the result of a product is 0, at least one of its factors is 0.

Conclusie

When the result of a product is 0, at least one of its factors is 0.

So we know that if

Then                    or

A⋅B=0

A=0

B=0

How do we use this to solve equations?

We can solve equations like

(x−1)(x+3)=0

then

                           or 

(x−1)(x+3)=0

x−1=0

x+3=0

                           or 

                             or

(x−1)(x+3)=0

x−1=0

x+3=0

x=1

x=−3

then

                           or 

5x(x−10)=0

5x=0

x−10=0

then

                         or 

                         or

5x(x−10)=0

5x=0

x−10=0

x=0

x=10

Two more examples

x​2​​+3x+2=0

x​2​​−12x=0

Two routes

100−4x​2​​