Datrys (2a-1)^2-9b^2-(2a-3b+1)^2

$$( 2 a - 1 ) ^ { 2 } - 9 b ^ { 2 } - ( 2 a - 3 b + 1 ) ^ { 2 }$$

Enrhifo

$$12ab-8a-18b^{2}+6b$$

Camau Ateb

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

$$4a^{2}-4a+1-9b^{2}-\left(2a-3b+1\right)^{2}$$

Sgwâr 2a-3b+1.

$$4a^{2}-4a+1-9b^{2}-\left(4a^{2}-12ab+4a+9b^{2}-6b+1\right)$$

I ddod o hyd i wrthwyneb 4a^{2}-12ab+4a+9b^{2}-6b+1, dewch o hyd i wrthwyneb pob term.

$$4a^{2}-4a+1-9b^{2}-4a^{2}+12ab-4a-9b^{2}+6b-1$$

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

$$-4a+1-9b^{2}+12ab-4a-9b^{2}+6b-1$$

Cyfuno -4a a -4a i gael -8a.

$$-8a+1-9b^{2}+12ab-9b^{2}+6b-1$$

Cyfuno -9b^{2} a -9b^{2} i gael -18b^{2}.

$$-8a+1-18b^{2}+12ab+6b-1$$

Tynnu 1 o 1 i gael 0.

$$-8a-18b^{2}+12ab+6b$$

Ehangu

$$12ab-8a-18b^{2}+6b$$

Camau Ateb

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

$$4a^{2}-4a+1-9b^{2}-\left(2a-3b+1\right)^{2}$$

Sgwâr 2a-3b+1.

$$4a^{2}-4a+1-9b^{2}-\left(4a^{2}-12ab+4a+9b^{2}-6b+1\right)$$

I ddod o hyd i wrthwyneb 4a^{2}-12ab+4a+9b^{2}-6b+1, dewch o hyd i wrthwyneb pob term.

$$4a^{2}-4a+1-9b^{2}-4a^{2}+12ab-4a-9b^{2}+6b-1$$

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

$$-4a+1-9b^{2}+12ab-4a-9b^{2}+6b-1$$

Cyfuno -4a a -4a i gael -8a.

$$-8a+1-9b^{2}+12ab-9b^{2}+6b-1$$

Cyfuno -9b^{2} a -9b^{2} i gael -18b^{2}.

$$-8a+1-18b^{2}+12ab+6b-1$$

Tynnu 1 o 1 i gael 0.

$$-8a-18b^{2}+12ab+6b$$