JIT compilation failed for NgModule class AppModule

JIT compilation failed for NgModule class AppModule {
}
getCompilerFacade @ core.js:4036
get @ core.js:26953
getNgModuleDef @ core.js:1117
assertNgModuleType @ core.js:1296
compileNgModuleFactory__POST_R3__ @ core.js:29106
bootstrapModule @ core.js:29357
4431 @ main.ts:11
__webpack_require__ @ bootstrap:19
__webpack_exec__ @ main.js:234
(anonymous) @ main.js:235
__webpack_require__.O @ chunk loaded:23
(anonymous) @ main.js:236
webpackJsonpCallback @ jsonp chunk loading:33
(anonymous) @ main.js:1

Uncaught Error: The NgModule 'AppModule' needs to be compiled using the JIT compiler, but '@angular/compiler' is not available.

JIT compilation is discouraged for production use-cases! Consider using AOT mode instead.
Alternatively, the JIT compiler should be loaded by bootstrapping using '@angular/platform-browser-dynamic' or '@angular/platform-server',
or manually provide the compiler with 'import "@angular/compiler";' before bootstrapping.
at getCompilerFacade (core.js:4055)
at Function.get (core.js:26953)
at getNgModuleDef (core.js:1117)
at assertNgModuleType (core.js:1296)
at compileNgModuleFactory__POST_R3__ (core.js:29106)
at PlatformRef.bootstrapModule (core.js:29357)
at Module.4431 (main.ts:11)
at __webpack_require__ (bootstrap:19)
at __webpack_exec__ (main.js:234)
at main.js:235





to solve this issue go to app.module.ts
& remove anyone from following
import { FormBuilder} from '@angular/forms';
import { FormGroup} from '@angular/forms';
import { FormControl} from '@angular/forms';
import { Validators } from '@angular/forms';
& its class