Volume of rectangle = length x breadth x height. To evaluate volume of rectangular boxes, multiply all the monomials.
(i) \(5a \times 3a^2 \times 7a^4\)
\(= (5 \times 3 × 7) (a × a^2 × a^4 ) \)
\(= 105a^7\)
(ii) \( 2p \times 4q \times 8r \)
\(= (2 × 4 × 8 ) (p × q × r ) \)
\(= 64pqr\)
(iii) \(y \times 2x^2y × 2xy^2\)
\(=(1 × 2 × 2 )( x × x^2 × x × y × y × y^2 ) \)
\(= 4x^4y^4\)
(iv) \(a \times 2b \times 3c \)
\(= (1 × 2 × 3 ) (a × b × c)\)
\(= 6abc\)
First monomial → Second monomial ↓ | 2x | –5y | 3x2 | – 4xy | 7x 2 y | –9x 2 y 2 |
2x | 4x2 | . . . | . . . | . . . | . . . | . . . |
–5y | . . . | . . . | -15x2y | . . . | . . . | . . . |
3x2 | . . . | . . . | . . . | . . . | . . . | . . . |
– 4xy | . . . | . . . | . . . | . . . | . . . | . . . |
7x 2 y | . . . | . . . | . . . | . . . | . . . | . . . |
–9x2 y2 | . . . | . . . | . . . | . . . | . . . | . . . |