Datrys (2a+1)^3-2a(2a+1)^2-(2a)^2-1

$$( 2 a + 1 ) ^ { 3 } - 2 a ( 2 a + 1 ) ^ { 2 } - ( 2 a ) ^ { 2 } - 1$$

Enrhifo

$$4a$$

Camau Ateb

Defnyddio'r theorem binomaidd \left(p+q\right)^{3}=p^{3}+3p^{2}q+3pq^{2}+q^{3} i ehangu'r \left(2a+1\right)^{3}.

$$8a^{3}+12a^{2}+6a+1-2a\left(2a+1\right)^{2}-\left(2a\right)^{2}-1$$

Defnyddio'r theorem binomaidd \left(p+q\right)^{2}=p^{2}+2pq+q^{2} i ehangu'r \left(2a+1\right)^{2}.

$$8a^{3}+12a^{2}+6a+1-2a\left(4a^{2}+4a+1\right)-\left(2a\right)^{2}-1$$

Ehangu \left(2a\right)^{2}.

$$8a^{3}+12a^{2}+6a+1-2a\left(4a^{2}+4a+1\right)-2^{2}a^{2}-1$$

Cyfrifo 2 i bŵer 2 a chael 4.

$$8a^{3}+12a^{2}+6a+1-2a\left(4a^{2}+4a+1\right)-4a^{2}-1$$

Defnyddio’r briodwedd ddosbarthu i luosi -2a â 4a^{2}+4a+1.

$$8a^{3}+12a^{2}+6a+1-8a^{3}-8a^{2}-2a-4a^{2}-1$$

Cyfuno 8a^{3} a -8a^{3} i gael 0.

$$12a^{2}+6a+1-8a^{2}-2a-4a^{2}-1$$

Cyfuno 12a^{2} a -8a^{2} i gael 4a^{2}.

$$4a^{2}+6a+1-2a-4a^{2}-1$$

Cyfuno 6a a -2a i gael 4a.

$$4a^{2}+4a+1-4a^{2}-1$$

Cyfuno 4a^{2} a -4a^{2} i gael 0.

$$4a+1-1$$

Tynnu 1 o 1 i gael 0.

$$4a$$

Ehangu

$$4a$$

Camau Ateb

Defnyddio'r theorem binomaidd \left(p+q\right)^{3}=p^{3}+3p^{2}q+3pq^{2}+q^{3} i ehangu'r \left(2a+1\right)^{3}.

$$8a^{3}+12a^{2}+6a+1-2a\left(2a+1\right)^{2}-\left(2a\right)^{2}-1$$

Defnyddio'r theorem binomaidd \left(p+q\right)^{2}=p^{2}+2pq+q^{2} i ehangu'r \left(2a+1\right)^{2}.

$$8a^{3}+12a^{2}+6a+1-2a\left(4a^{2}+4a+1\right)-\left(2a\right)^{2}-1$$

Ehangu \left(2a\right)^{2}.

$$8a^{3}+12a^{2}+6a+1-2a\left(4a^{2}+4a+1\right)-2^{2}a^{2}-1$$

Cyfrifo 2 i bŵer 2 a chael 4.

$$8a^{3}+12a^{2}+6a+1-2a\left(4a^{2}+4a+1\right)-4a^{2}-1$$

Defnyddio’r briodwedd ddosbarthu i luosi -2a â 4a^{2}+4a+1.

$$8a^{3}+12a^{2}+6a+1-8a^{3}-8a^{2}-2a-4a^{2}-1$$

Cyfuno 8a^{3} a -8a^{3} i gael 0.

$$12a^{2}+6a+1-8a^{2}-2a-4a^{2}-1$$

Cyfuno 12a^{2} a -8a^{2} i gael 4a^{2}.

$$4a^{2}+6a+1-2a-4a^{2}-1$$

Cyfuno 6a a -2a i gael 4a.

$$4a^{2}+4a+1-4a^{2}-1$$

Cyfuno 4a^{2} a -4a^{2} i gael 0.

$$4a+1-1$$

Tynnu 1 o 1 i gael 0.

$$4a$$