Leysa 3/4(2-5i)+1/2(3+1/2i)?

$$\frac { 3 } { 4 } ( 2 - 5 i ) + \frac { 1 } { 2 } ( 3 + \frac { 1 } { 2 } i ) ?$$

Meta

$$3-\frac{7}{2}i=3-3.5i$$

Lausnarskref

Margfaldaðu \frac{3}{4} sinnum 2-5i.

$$\frac{3}{4}\times 2+\frac{3}{4}\times \left(-5i\right)+\frac{1}{2}\left(3+\frac{1}{2}i\right)$$

Margfaldaðu í \frac{3}{4}\times 2+\frac{3}{4}\times \left(-5i\right).

$$\frac{3}{2}-\frac{15}{4}i+\frac{1}{2}\left(3+\frac{1}{2}i\right)$$

Margfaldaðu \frac{1}{2} sinnum 3+\frac{1}{2}i.

$$\frac{3}{2}-\frac{15}{4}i+\frac{1}{2}\times 3+\frac{1}{2}\times \left(\frac{1}{2}i\right)$$

Margfaldaðu í \frac{1}{2}\times 3+\frac{1}{2}\times \left(\frac{1}{2}i\right).

$$\frac{3}{2}-\frac{15}{4}i+\left(\frac{3}{2}+\frac{1}{4}i\right)$$

Sameinaðu raunhluta og þverhluta.

$$\frac{3}{2}+\frac{3}{2}+\left(-\frac{15}{4}+\frac{1}{4}\right)i$$

Leggðu saman.

$$3-\frac{7}{2}i$$

Raunhluti

$$3$$

Lausnarskref

Margfaldaðu \frac{3}{4} sinnum 2-5i.

$$Re(\frac{3}{4}\times 2+\frac{3}{4}\times \left(-5i\right)+\frac{1}{2}\left(3+\frac{1}{2}i\right))$$

Margfaldaðu í \frac{3}{4}\times 2+\frac{3}{4}\times \left(-5i\right).

$$Re(\frac{3}{2}-\frac{15}{4}i+\frac{1}{2}\left(3+\frac{1}{2}i\right))$$

Margfaldaðu \frac{1}{2} sinnum 3+\frac{1}{2}i.

$$Re(\frac{3}{2}-\frac{15}{4}i+\frac{1}{2}\times 3+\frac{1}{2}\times \left(\frac{1}{2}i\right))$$

Margfaldaðu í \frac{1}{2}\times 3+\frac{1}{2}\times \left(\frac{1}{2}i\right).

$$Re(\frac{3}{2}-\frac{15}{4}i+\left(\frac{3}{2}+\frac{1}{4}i\right))$$

Sameinaðu raunhluta og þverhluta í \frac{3}{2}-\frac{15}{4}i+\frac{3}{2}+\frac{1}{4}i.

$$Re(\frac{3}{2}+\frac{3}{2}+\left(-\frac{15}{4}+\frac{1}{4}\right)i)$$

Leggðu saman í \frac{3}{2}+\frac{3}{2}+\left(-\frac{15}{4}+\frac{1}{4}\right)i.

$$Re(3-\frac{7}{2}i)$$

Raunhluti 3-\frac{7}{2}i er 3.

$$3$$