i(3i+6)(2−7i)

= (3i² + 6i)(2 - 7i) distributive property

= 6i² - 21i³ + 12i - 42i² foil method

= -21i³ - 36i² + 12i combined like terms

= -21(i²)(i) - 36(-1) + 12i broke down i³ and simplified i² to be -1

= -21(-1)(i) + 36 + 12i simplified i² to be -1

= 21i + 36 + 12i multiplied

= 36 + 33i combined like terms

*McGenius*

**
**