√(9-4√2) *(1+2√2) решите

√ ( (2√2)² - 2 * 2√2 * 1 + 1²)  * (1 + 2√2) = √( 2√2-1)² * (1+2√2)=|2√2-1| * (1+2√2) = (2√2-1) * (2√2+1) = (2√2)² - 1² = 8 - 1 = 7