import React, { Component } from 'react'
import MathRenderer from 'math-renderer'
import 'katex/dist/katex.min.css'

class Example extends Component {
  render () {
    return (
      <MathRenderer value={"Inline expression $\\int_0^\\infty x^2 dx$"} />
    )
  }
}

Or

class Example2 extends Component {
  render () {
    return (
      <MathRenderer value={"Block expression $$\\int_0^\\infty x^2 dx$$"} />
    )
  }
}