div {
background: pink;
width: 280px;
height: 60px;
padding: 20px;
margin: 10px;
float:left;
}
.ex1 {border-radius: 20px 50px 30px 15px}
.ex2 {border-radius: 20px 50px 30px }
.ex3 {border-radius: 20px 50px}
.ex4 {border-radius: 20px}
<!DOCTYPE html>
<html lang="ko">
<head></head>
<body>
<div class="ex1">border-radius: 20px 50px 30px 15px;</div>
<div class="ex2">border-radius: 20px 50px 30px;</div>
<div class="ex3">border-radius: 20px 50px;</div>
<div class="ex4">border-radius: 20px;</div>
</body>
</html>