Correct

相反相成

/ xiāngfǎn xiāng chéng / 
Strokes

Example

Definition

(of two things) be both opposite and complementary to each other; oppose and yet complement each other

1
Shībàishìchénggōngzhīmǔ
失败是成功之母
  
,
shuōmíng
说明
èrzhě
二者
shì
是
xiāngfǎnxiāngchéng
相反相成
de
的
  
。

It is a paradox that failure is the mother of success.