(3+9i)(-9+7i)= eching

$$( 3 + 9 i ) ( - 9 + 7 i ) =$$

Baholash

$$-90-60i$$

Yechim qadamlari

Binomlarni ko‘paytirgandek 3+9i va -9+7i murakkab sonlarni ko‘paytiring.

$$3\left(-9\right)+3\times \left(7i\right)+9i\left(-9\right)+9\times 7i^{2}$$

Ta’rifi bo‘yicha, i^{2} – bu -1.

$$3\left(-9\right)+3\times \left(7i\right)+9i\left(-9\right)+9\times 7\left(-1\right)$$

Ko‘paytirishlarni bajaring.

$$-27+21i-81i-63$$

Real va mavhum qismlarni birlashtiring.

$$-27-63+\left(21-81\right)i$$

Qo‘shishlarni bajaring.

$$-90-60i$$

Ashyoviy qism

$$-90$$

Yechim qadamlari

Binomlarni ko‘paytirgandek 3+9i va -9+7i murakkab sonlarni ko‘paytiring.

$$Re(3\left(-9\right)+3\times \left(7i\right)+9i\left(-9\right)+9\times 7i^{2})$$

Ta’rifi bo‘yicha, i^{2} – bu -1.

$$Re(3\left(-9\right)+3\times \left(7i\right)+9i\left(-9\right)+9\times 7\left(-1\right))$$

3\left(-9\right)+3\times \left(7i\right)+9i\left(-9\right)+9\times 7\left(-1\right) ichidagi ko‘paytirishlarni bajaring.

$$Re(-27+21i-81i-63)$$

-27+21i-81i-63 ichida real va mavhum qismlarni birlashtiring.

$$Re(-27-63+\left(21-81\right)i)$$

-27-63+\left(21-81\right)i ichida qo‘shishlarni bajaring.

$$Re(-90-60i)$$

-90-60i ning real qismi – -90.

$$-90$$