fix: nthRoots latexFunctions template string (#3427)

Author: aitee

src/utils/latex.js

@@ -143,7 +143,7 @@ export const latexFunctions = {
     2: undefined // use default template
   },
   nthRoot: { 2: '\\sqrt[${args[1]}]{${args[0]}}' },
-  nthRoots: { 2: '\\{y : $y^{args[1]} = {${args[0]}}\\}' },
+  nthRoots: { 2: '\\{y : y^${args[1]} = {${args[0]}}\\}' },
   pow: { 2: `\\left(\${args[0]}\\right)${latexOperators.pow}{\${args[1]}}` },
   round: {
     1: '\\left\\lfloor${args[0]}\\right\\rceil',

test/unit-tests/expression/node/FunctionNode.test.js

@@ -519,6 +519,9 @@ describe('FunctionNode', function () {
     const o = new OperatorNode('+', 'add', [c1, c2])
     const n3 = new FunctionNode(new SymbolNode('permutations'), [o])
     assert.strictEqual(n3.toTex(), '\\mathrm{permutations}\\left(4+5\\right)')
+
+    const n4 = new FunctionNode(new SymbolNode('nthRoots'), [c1, c2])
+    assert.strictEqual(n4.toTex(), '\\{y : y^5 = {4}\\}')
   })
 
   it('should have an identifier', function () {